2 Corinthians 2:17 For we are not as many, which corrupt the word of God: but as of sincerity, but as of God, in the sight of God speak we in Christ.
From the text it seems this existed from the times of the apostles, not just in our day. Perhaps it is easier to do today since we have an open toleration for relativism, but often it is far beyond that as those who do corrupt the word of God, do it deceptively preaching their very doctrines for truth. Walter Martin’s old book Kingdom of the Cults is a great place to start, these seem to address only the obvious ones.
This becomes doubly bad if it is mixed with greed for “filthy lucre” as the KJV declares:
1Ti 3:3 Not given to wine, no striker, not greedy of filthy lucre; but patient, not a brawler, not covetous;
1Ti 3:8 Likewise must the deacons be grave, not doubletongued, not given to much wine, not greedy of filthy lucre;
Tit 1:7 For a bishop must be blameless, as the steward of God; not selfwilled, not soon angry, not given to wine, no striker, not given to filthy lucre;
Tit 1:11 Whose mouths must be stopped, who subvert whole houses, teaching things which they ought not, for filthy lucre’s sake.
1Pe 5:2 Feed the flock of God which is among you, taking the oversight thereof, not by constraint, but willingly; not for filthy lucre, but of a ready mind;
2 Corinthians 2:17 John Gill writes:
For we are not as many, which corrupt the word of God – God has made Us sufficient for these things by giving us his own pure doctrine, the ministry of reconciliation, which we conscientiously preserve and preach; and we act, not like many among you, who, having received that doctrine, corrupt it; mingling with it their own inventions, and explaining away its force and influence, so as to accommodate it to men of carnal minds.
The word καπηλευοντες, from καπηλος, a tavernkeeper, signifies acting like an unprincipled vintner; for this class of men have ever been notorious for adulterating their wines, mixing them with liquors of no worth, that thereby they might increase their quantity; and thus the mixture was sold for the same price as the pure wine. Isa 1:22, Thy wine is mixed with water, the Septuagint thus translate: οἱ καπηλοι σου μισγουσι τον οινον ὑδατι· “Thy vintners mix thy wine with water;” that is, thy false prophets and corrupt priests adulterate the word of God, and render it of none effect, by their explanations and traditions.
The word has been used, both among the Greeks and Latins, to signify a prostitution of what was right and just, for the sake of gain. So Herodian, lib. vi. cap. 11; Ειρηνην χρυσιου καπηλευοντες, “Making peace for money.” So cauponari bellum is, “To make war for money.” In short, the word is used to signify any artifice employed to get gain by making a thing look more or better than it is; or mingling that which is excellent with what is not so to promote the gain of the adulterater.
It is used by Aristophanes, Plut. Act. iv., scene 5, ver. 1064, to express an old woman who was patched and painted to hide her deformity.
Ου δητ’, επει μεν νυν καπηλικως εχει·
Ει δ’ εκπλυνειται τουτο το ψιμυθιον,
Οψει καταδηλα του προσωπου γε τα ῥακη.
Not at all; the old woman is painted:
If the paint were washed off, then you
Would plainly see her wrinkled face.
Where see the note of the Scholiast, who observes that the term is applied to those who deal in clothes, patching, mending, etc., as well as to those who mix bad wine with good. Καπηλικως εχει· Πανουργικως· επει οἱ καπηλοι χριειν και αναποιειν τα ἱματια ειωθασι, και τον οινον δε νωθυλευουσι, συμμιγνυντες αυτῳ σαπρον. Vid. Kusteri Aristoph., page 45.
BTW we might do well to review again what the WCF says about the word of God we have in our Bibles, you can find the text here:
Confession of Faith