A.T. Robertson Commentary Luke 6:33

"And if ye do good to them that do good to you, what thank have ye? for even sinners do the same." — Luke 6:33 (ASV)

Do good (αγαθοποιητε). Third-class condition, εαν and present subjunctive. This verb not in old Greek, but in LXX.

Even sinners (κα ο αμαρτωλο). Even the sinners, the article distinguishing the class. Matthew 5:46 has "even the publicans" and 5:47 "even the Gentiles." That completes the list of the outcasts for "sinners" includes "harlots" and all the rest.