There is no explicit indication prior to Romans 2:17 that Paul has the Jews in mind.
But there are good reasons for thinking that Paul had the Jews in mind starting in verse 1 of chapter 2 -
Throughout this section of the Roman letter, Paul seems to address
himself to only two groups of people: Jews and Gentiles
Romans
Romans
3:9
-
What shall we conclude then? Are we [Jews] any better [than the Gentiles]? Not
at all! We have already made the charge that Jews and Gentiles alike are all under sin.
The attitude of moral superiority described in this passage (2:1ff.) is much like
the attitude that the Jews had toward the Gentiles (as indicated in verses
18ff.)
The way in which the name Jew is introduced in verse 17 does not suggest that Paul is
turning his attention to a different group of people:
2:1 You, therefore, have no excuse . . .
2:3 So when you, a mere man . . .
2:4 Or do you show contempt . . .