Be not ye therefore partakers with them - Since these things displease God and expose to his wrath, avoid them.

Be not ye therefore partakers with them - Do not act as your fellow citizens do; nor suffer their philosophy, to it in vain words, κενοις λογοις, with empty and illusive doctrines, to lead you astray from the path of truth.
That there was much need for such directions and cautions to the people of Ephesus has been often remarked. It appears, from Athenaeus, that these people were addicted to luxury, effeminacy etc. He tells us that the famous Aspasia, who was herself of the Socratic sect, brought a vast number of beautiful women into Greece, and by their means filled the country with prostitutes, και επληθυνεν απο των ταυτης ἑταιριδων ἡ Ελλας, lib. xiii. cap. 25. Ibid. cap. 31, he observes that the Ephesians had dedicated temples ἑταιρᾳ Αφροδιτῃ, to the prostitute Venus; and again, cap. 32, he quotes from Demosthenes, in Orat. contra Neaeram: τας μεν ἑταιρας ἡδονης ἑνεκα εχομεν, τας δε παλλακας της καθ' ἡμεραν παλλακειας, τας δε γυναικας του παιδοποιεισθαι γνησιως, και των ενδον φυλακα πιστην εχειν· "We have whores for our pleasure, harlots for daily use, and wives for the procreation of legitimate children, and for the faithful preservation of our property." Through the whole of this 13th book of Athenaeus the reader will see the most melancholy proofs of the most abominable practices among the Greeks, and the high estimation in which public prostitutes were held; the greatest lawgivers and the wisest philosophers among the Greeks supported this system both by their authority and example. Is it not in reference to their teaching and laws that the apostle says: Let no man deceive you with vain words?

(3) Be not ye therefore partakers with them.
(3) Because we are most ready to follow evil examples, therefore the apostle warns the godly to always remember that the others are but as it were darkness, and that they themselves are as it were light. And therefore the others commit all evils (as men are accustomed to do in the dark), but they ought not to follow their examples, but rather (as the property of the light is) reprove their darkness, and to walk in such a way (having Christ that true light going before them) as it becomes wise men.

Be not ye therefore partakers with them. In their sins, and acts of disobedience; by keeping needless company with them; by abetting and encouraging sinful practices; by conniving at them, and not reproving for them; or by committing the same things.

Here fellowship with wicked workers is forbidden; in Ephesians 5:11, with their wicked works.