I've been accumulating a list of all the traditional religious terms that are either not in the Bible or have become much more religiously loaded than they were in the original text.
I've found that many religious traditions are based on or reinforced by religious terms. Knowing religious word origins can help to separate out what terminology is based on actual scripture and what is not, so that doctrines and traditions of men are not made out of religious terminology.
"religion/religious" = Greek "θρησκεια/θρησκος" = "threskeia/threskos" = ceremonial/ritual observance (Acts 26:5, Col 2:18, James 1:26-27), never portrayed in any positive light in the New Testament (James uses the term facetiously; helping widows/orphans and keeping oneself from being polluted by the world is certainly not a ceremonial/ritual observance).
"church": Different meaning than in the New Testament. Greek "εκκλησια" = "ek-klesia" = "out-calling," a completely secular term referring to a group or class of people called-out, and if they assemble it is because of being "called out." In Acts 19, the "out-called" mob (called out by Demetrius the silversmith and his angry cohorts), and also the legal "out-called" proconsuls that the city clerk told the mob that they should have instead appealed to, were both called "ek-klesia" (= "church"??). See What is "church" according to the scriptures?
"prayer": Today commonly defined differently than in the New Testament. In the New Testament, the usual word is "προσευχη" = "pros-euche" = "toward-vow/wish/will" which is a declaration of intent towards something. There are an assortment of other common words used less often, which are just the normal words for ask, request, petition, supplication, beseech, plead, intercede, implore, etc., some of which at various times are rendered "pray" in some various translations. There is no word in the New Testament that actually means "talk to God" or "ask God." See What is "prayer" according to the scriptures?.
"repent/repentance" = "μετανοω/μετανοια" = "metanoO/metanoia" (verb/noun), from "μετα" = "change," and "νους" = "mind/thinking," and that's all it means. Context must be read to find out what it is that a person should change their mind/thinking about, or have a change of mind/thinking about! Today it is a loaded religious term, where "repent" = "feel remorseful, very remorseful, very contrite, and try very, very hard to never, ever sin again" (usually in an old covenant mindset); however, "sin" isn't intrinsically implied by the word "repent" itself. See What is "repentance" according to the scriptures?.
"sin" = "αμαρτια/αμαρτανω" = "[h]amartia/[h]amartano" = "failure/fail, fault/err" (LSJ: noun/verb). The typical modern religious meaning is to "disobey a command of God" (i.e. do some bad thing in God's sight), which is an Old Covenant concept, but the Greek word (LSJ: noun/verb) refers to any "failure" or "fault." That's actually a much higher standard, since you can also "fail" by doing nothing at all.
"forgive/forgiveness" = "αφηιμι/αφεσις" = "aphiemi/aphesis" is constructed from a combination of "αφ/απο" (Strong's G575, "aph/apo"), which is the preposition or prefix for "off-from/away" (i.e. something positionally "off" something else, or "away" "from" it), and the verb ιημι (see LSJ #51600, "iemi") which means "release" or "let-go/send" in an active sense. So, you have the sense of release/let-send/go-off-from/away. Forgiveness is not a feeling about people's sins. It is a matter of deciding to "leave it" and "let it go," "off/away" from you. Sometimes this word has been used in an overly religious or sentimental way, when it is neither. See What is "forgiveness" according to the scriptures?"
"baptize/ism" = "βαπτιζω/βαπτισμα" = "baptizo/baptisma" = modern religious transliteration (Roman letter for Greek letter, sound for sound). The word means immerse/immersion, and has no intrinsic religious meaning. In the kitchen you immerse (baptize) your dirty dishes in a tub of water to get the dried-on tomato sauce off. If it is a person getting "immersed," context must be looked at to see what they are getting "immersed" into (body of Christ, Holy Spirit, "his death," water, etc.) See Acts 2:38 "baptism" analysis ("immersed" into pardon of sins, not water), and 1 Peter 3:21 "baptism" analysis (the wicked being "immersed" to death in the days of Noah).
"righteous" = "justified": From Greek "δικαιος" = "dikaios" = "justice" which is one root word that is translated into the two possible English words. The English word "righteous" often has more of a religious meaning, but the Greek word just means to be "justified."
"faith" = "belief" = Greek "πιστ__" = "pist__" which is one word in the Greek, not two. Faith = belief. To have faith is to believe. "Faith" has become much more religiously loaded than it was, even to the point of being mystical. But it is just your confidence in something, like how you are confident that the chair that you are sitting in right now will not collapse underneath you. See Faith formulas.
"save/salvation/savior": This English term has become overly religious. It is from "σωζω/σωτηρια/σωτηρ" = "sozo/soteria/soter" which is not religious, and just means to (verb) rescue, deliver, protect, or (noun) deliverance/protection, or (person) someone who delivers or protects. Context must be looked at to determine what calamity or malady is being referring to, whether "rescued" from judgment and the wrath of God to come (because of having been guilty of sin), or "rescued" from affliction, or etc. In other words, if you say you are "saved," then you must specify what are you "saved" from. "Saved" is a modern religious buzzword, but you are "saved" from something, not just "saved." If the fire department comes and rescues you from a burning house, then you were "saved" from being burned up with the house and the fireman is the "savior" who effected that "salvation."
"born again": This term actually originates from what Nicodemus naively asked Jesus in John 3:4, when he questioned how a person could be born a second time when he was old. The exact phrase Jesus used was literally "γεννηθη ανωθεν" = "gennethe anothen" = "generated/begotten up-ly/new-ly." The word "again" is not actually in the original text ("again" would have been "παλιν" = "palin," if that word were used). See John 3:1-15, color coded.
"grace": Often has more religious overtones than necessary. The root word "χαρις" = "charis" = "favor."
"spiritual gift(s)": Not even in the Bible, despite all the religious fuss about it. The word is "χαρισμα(τα)" = "charis-ma(ta)" = "grace-effect(s)/working(s)/manifestation(s)." Just adds the -μα(τα) = "ma(ta)" suffix to the word "grace/favor" (The -τα = "-ta" makes it plural). See Spiritual gifts: Not even in the original text.
"spirit" = "πνευμα" = "pneu-ma" = literally "blow-effect" (wind, breath). See Gen 2:7 (LXX). It can be traced to the "effect" of God breathing the breath of aliveness ("ζωη" = "zoe" = "life" = being "alive") into the man. This word has become very religious and mystical, when it is just a best-effort attempt to describe something non-physical with physical terminology, a living being apart from the body, or without one (demons are also often referred to as "spirits"). It is just the essence of the life force/being that one has and is. (See article on Tripartite dogma)
"soul" = "ψυχη" = "psuche," = "life," as in the "life you live," not to be confused with "ζωη" = "zoe" = "life" = being "alive" (as opposed to "not alive" = "dead"), or "πνευμα" = "pneu-ma" = "blow-effect," where "pneuma" is that within you which caused/causes/drives "the life you live." See Gen 2:7 (LXX), where it is the "life" that a man lives out as a result of God having breathed the breath of "life" ("zoe" = aliveness) into the first man (and hence the rest of us, who are his children). This word has become very religious and mystical, when it is not. It can mean just generically anything/everything, any/all aspects about your life and being, the "life you live," so is very broad in its meaning and application, and you have to look at the context to see how it is used in each place. (See article on Tripartite dogma)
"apostle" = "αποστολος" = "apo-stolos" = one "sent off" (the noun form) on some commission, but a very general nown or verb that does not carry the special, high and lofty religious meaning given to it today. Herod the Great sent apostles to kill all the babies, Jesus "sent" the demons into the pigs, Jesus was an apostle, John the Baptist was an apostle, Epaphroditus was an apostle, Herod Antipas "sent off" an executioner to bring back the head of John the Baptist, Jesus talks about "sending forth" angels in his parables, a man should not write a certificate of divorce and "send off" his wife, the Pharisees "sent off" people to trap Jesus in his words, the Holy Spirit was an apostle at Pentecost, etc. The "twelve" hand-picked disciples of Jesus were designated "apostles" simply on account of the fact that they were "sent off" two by two in Matt 10:1-5, Mark 6:7,30 Luke 9:1-2,10, by Jesus, and the label stuck, so from that point on they were labeled the "sent-off-ones." The apostle Paul was the "apostle" Paul because he was sent off-out (εξαποστελω = "ex-apo-stelo," Acts 22:21) to the Gentiles/nations by Jesus.
"prophet" = "προφητ__" = "pro-phet__" = "before-averer" or "fore-teller"
"elder" = "πρεσβυτερ__" = "presbyter__" = old/senior person. Elders are mature (in age and/or faith). They oversee and shepherd. (Compare 1 Tim 3, Tit 1, 1 Pet 5, and Acts 20:28.)
"overseer" = "επισκοπ__" = "epi-scope" = "over/upon-look". Someone who over-sees, a very general term. This is what elders are supposed to do (see previous word above). Likewise "pastors" (shepherds). (Compare 1 Tim 3, Tit 1, 1 Pet 5, and Acts 20:28.)
"bishop": This is just a religious, institutionalized term for "overseer," from Old English roots. So anyone, religious or secular, tasked with overseeing anything, spiritual or secular, important or mundane, is a "bishop." The manager at the McDonald's restaurant and the foreman supervising the construction workers fixing up the road are both "bishops." Think about that.
"pastor": Purely religious term originating from Latin ("pastor" = "shepherd"), only occurring once in English translation in the Bible, in Eph 4:11. The actual Greek word is "ποοιμην" = "poimen" = "shepherd," a common term, but the religious label was invented and translated as such only in Eph 4:11, beginning with the Protestants' Geneva Bible and the Church of England's King James Bible. Previous to that, Wycliffe, Tyndale, et al. translated it "shepherd." "Elders" "shepherd." "Overseers" "shepherd." (Compare 1 Tim 3, Tit 1, 1 Pet 5, and Acts 20:28.)
"deacon": Purely religious term. Transliterated from the common word "διακον__" = "diakon__" = "servant" or "dispenser". Servant/service/serve/dispense is a non-religious, generic term very broadly and frequently used. Any servant of any kind, religious or not, Christian or secular, is a "diakon__."
"minister, Minister, ministry": Purely religious term. The word is the common word "διακον__" = "diakon__" = "servant" or "dispenser," or the word "λειτουργ__" = "leitourg__" = public servant/worker. These are non-religious, generic terms very broadly and frequently used. Any servant of any kind, religious or not, Christian or secular, is a "diakon__," and a person officially tasked to work among/for the people is a "leitourg__."
"liturgy/liturgical": Religious term that can be traced back to late Latin "liturgia," which was based on ancient Greek "λειτουργια" = "leitourgia" and related words, which were originally secular terms referring to a public worker/servant/work/service.
"clergy/cleric": Religious term that can be traced back to Latin "clericus," originally having to do with being "learned men." Not in Bible.
"ordain/ordination": 13th century English word from a Latin root ("put in order"). Not in Bible.
"reverend": 16th century religious word from a Latin root; one "worthy of respect," a "person to be revered." Not in Bible.
"mission, missions, missionary": A generic English word made into a religious one, but not in the Bible. The English word is from a Latin root, which just refers to a strategic task/project that is to be accomplished, or someone sent or dispatched for such a task.
"preach/preacher": Purely religious term. There is a word in the Greek, "κηρυσσο/κηρυξ" = "kerusso/kerux" = "proclaim/proclaimer" or "herald/herald-er," and a few other words based on the root "__αγγελ__" = "__aggel__" = "message/messenger," but these are all very generic and mean nothing more than that. If you go by any of these Greek words used, there were no "preachers" in the Bible, and neither Jesus nor any of the original twelve, nor the apostle Paul, nor anyone else is ever cited as having ever "preached" a single sermon in the Bible! Today it has become religious terminology for a class of religious professionals (usually clergy) and a religious act that they perform in a religious institutional program in front of a religious audience. But all the New Testament ever talks about is "proclaiming" or "heralding" the "message" in the various many passages, which is obviously what all of us are supposed to do, wherever, whenever, to anyone we happen to meet.
"sermon": Purely religious term, invented around the 11th-13th century, from a Latin root. Not in Bible. If it wasn't religious, it would be called a "lecture," an "oration," a "speech," or a "talk."
"worship": Different today than in the New Testament. Today "worship" has become synonymous with "music," yet the two are never directly connected or associated with one another anywhere in the New Testament! New Covenant "worship" is mentioned only once, where it is defined/re-framed by Jesus, in John 4:20-24 "...in spirit and in truth...," as opposed to where/how. (Note: "προσκυνεω," = "proskuneo" = "worship" is not to be confused with the word used in Rom 12:1, "λατρεια" = "latreia," which is not "worship" but "service/business/duty.") The typical, modern, popular concept of "worship" embraces either an old covenant mentality, a pagan mentality, or is redefined to refer to connecting with God using musical expression and experience. See What is "worship," according to the scriptures?
"Christ" = "χριστος" = "christos" = "anointed." "Anointed" literally refers to rubbing with something like oil. When referring to Jesus specifically, he would be the prophesied one who was anointed king of Israel, Jesus the "anointed." It isn't his last name or surname.
"Christian" = "anointed-ian." We are of the "anointed," because of who we are in Christ, the "anointed" one, causing us to be "anointed" as well. Be aware that the label "Christian" is used only two times in the Bible!
"anointed": Rubbed with something like oil. This has become a mystical, religious term, but it just means that someone or something has been ceremonially marked for some purpose by someone with the authority to do so. See this three-minute video for more.
"anointing": Having the effect of having been rubbed with something like oil. This has become a mystical, religious term, but it just means that someone or something still has the ceremonial mark of having been anointed. See this three-minute video for more.
"impart" = "μεταδω" = "meta-do" just the generic word for "share," occurring five times: Luke 3:11, Rom 1:11, Rom 12:8, Eph 4:28, 1 Thess 2:8.
"impartation": Not in Bible. You would expect that this would perhaps be there, somewhere, as the noun form of the verb "μεταδω" = "meta-do" = "share," which would be "μεταδομα" = "metadoma" = "share-effect" = "something shared," but that is nowhere to be found, so we can call the English noun form a purely religious invention.
"mantle" = "אַדֶּ֣רֶת" = an article of clothing that you wrap around yourself. Not even in the New Testament.
"sanctification": Religious buzzword, but is based on the Greek word "αγιος" = "[h]agios" = "holy," and its grammatical variations. The verb form would be "holy-ize" and the noun form of the verb form of the noun would be "holy-ization."
"sanctuary": This means "sacred place" or "holy place." The problem is that under the New Covenant a building or room cannot be "sacred," only we and our bodies that have been made so. But in modern terms it is a religious term that refers to the meeting room of a "church" building, where the "sermon" is "preached" by the clergy to the assembled laity, the "worship" music is played, group "prayers" are offered up, "tithes and offerings" are collected, and so on, which is based on either an Old Covenant mindset or pagan religious traditions.
"hell": This is an English religious word that has no one, direct, single counterpart in the Bible. Several different words are used in the Bible in different contexts: "Hades" in the Greek and "Sheol" in the Hebrew was just "the place where the dead went," and there wasn't much teaching about what happened to the dead, or about the place that they were in, other than that they were in that place, which was "unseen" (also literally implied by the word). "Gehenna" was the Valley of Hinnon," a garbage dump outside of Jerusalem where people threw their garbage and was continually burning, so it was used illustratively by Jesus eleven times, and once by James. "Tartarus" is only used once, in 2 Pet 2:4, and is a place mentioned also in 1 Enoch where angels were incarcerated. The "lake of fire" is spoken of several times in Revelation chapters 19-21. So there are many different words with different meanings, not one. (See disclaimer)
"angel" = "αγγελος" = "Aggelos" = "messenger," and context shows what kind of messenger (heavenly, demonic, human, etc.). There is actually no word for "angel" (heavenly being) in the Greek, so that has to be inferred from the context.
"gospel" = Old English word "gōd"+"spel" = "good+news" translated from Greek "ευ-αγγελ__" transliterated "ev-angel" = "well-message." Religious prescriptions and creeds are attached to the word, but it just means "good news."
"evangelist/ize" (transliteration) = "ευαγγελιστ__/ευαγγελιζ__" = "eu-aggelist__/eu-aggeliz__" = "well-messenger/message-ize."
"evangelism": The English noun form of the verb form "evangelize" (i.e. "the telling of the good news"). Not in Bible.
"eucharist" = "ευχαριστ__" = eu-charist__" = "well-favor" (verb) = "thank." The noun form is "gratitude/thankfulness/thanksgiving." This is not a religious word in the Bible, but was transliterated to create an English word that refers only to the Lord's Supper.
"communion" = "κοινωνια" = "koinonia" = "common-ization." In Koine (common) Greek it is not a religious term.
"fellowship" = "κοινωνια" = "koinonia" = "common-ization." In Koine (common) Greek it is not a religious term.
"tithe" = "δεκατη" = "dekate" = "tenth." That's arithmetic, a number: 1/10, as in 10%, not 9%, not 11%. The word has become a religious term, but it wasn't originally. There were certain Old Covenant regulations that required one tenth to be set aside, but this is irrelevant to the New Covenant, since it is never even mentioned in connection with the New Covenant. In fact, the tithe was "fulfilled" by Abraham long before the Old Covenant!
"thee/thou", etc.: Not in Bible. This is how everyone talked out on the streets during the Elizabethan era in England, even when they were cursing or drunk. But due to the persistence and ubiquitous nature of the King James Bible (even through its revisions), it eventually became a religious way to talk, the preferred religious way to pray and, especially, a reverent way to address God, to the extent that some more modern Bible versions kept this now-archaic language in their translations in specific places only specifically wherever God was addressed (such as the 1971 NASB, before they revised it in 1995 and eliminated the remaining places). Today Elizabethan English is, in a colloquial sense, only associated with religious expression. (Also see Regarding "KJV-only" activism)
"amen": This is just Hebrew for "truly," "surely," or "verily." Every time Jesus said "Truly I say to you..." he was using that word. But it has become a religious word. It has also become a ceremonial "end of prayer" delimiter.
"hallelujah": This is Hebrew for "praise Jah." It actually only occurs four times in one passage of the New Testament, in Rev 19:1-6.
Please let me know if you can think of any terms to add to the list! (I intend to update and refine the list as time goes on.)
Note: I am not trying to disparage the use of most of these words, even if you want to use them for sentimental reasons (although I find that I am using them less and less as time goes on). I am listing them so that we can recognize what the actual terminology of the Bible is and is not, so that doctrines of men are not built upon traditional religious terminology.
I grant this work to the public domain.