106 Three key (𝔓75 א* B) have “for” here, but it is unlikely that it was present originally. The addition of conjunctions, especially to the beginning of a clause, are typically suspect because they fit the pattern of Koine tendencies toward greater explicitness. has the word in brackets, indicating doubts as to its authenticity.
107 Most (A D L Θ Ξ Ψ f13 33 𝔐 lat) include γάρ (gar, “for”) following καί (kai, here translated “even”), but a few important (א B W 700 892* 1241 ) lack the conjunction. The inclusion of the conjunction seems to be motivated by clarity and should probably be considered inauthentic.
108 See the note on the word sinners in v. .

In other versions

And if you do good to those who do good to you, what benefit is that to you? For even sinners do the same.

And if you do good to those who are good to you, what credit is that to you? Even sinners do that.

If you do what is good to those who are good to you, what credit is that to you? Even sinners do that.

And if you do good only to those who do good to you, why should you get credit? Even sinners do that much!

And if you do good to those who do good to you, what kind of credit is that to you? Even the sinners do the same!

And if ye do good to them which do good to you, what thank have ye? for sinners also do even the same.

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