To understand 22:16 you have to start with 3:19. 3:19 reads, speaking to the nation of Israel: “Repent therefore and return, that your sins may be wiped away (blotted out, ‘exaleipho’), …” Repent and return are both Second person Plurals, Aorist Imperatives. Or, “All of you repent and all of you return [back to God] [with the result that] your sins will be blotted out (wiped away).” “Wiped away” is an Aorist Passive Infinitive. Or, “Your sins will be acted upon, blotted away, by God”—“They are to be acted upon by the Lord. He will cause them to be gone!” This is based on their repentance and their returning to God! Of course the message they are to believe in is the fact that “Christ should suffer” [for you], and this “He has thus fulfilled” (v. 18).

This idea then is picked up and applied to Paul here in 22:16. Ananias tells Paul that “it was appointed for him to know God’s will, and to hear an utterance from His mouth. Because he was to be a witness for Him to all men of what he has seen and heard” (v. 15).

22:16 reads from the Greek: “Having gotten up, you are to be baptized yourself, and yourself have your sins washed away, and called yourself upon His name.” All of these verbs show parallel action going on at once. The Middle Voice is used continually, “yourself.” They are all Aorist Tenses. It is all happening at once. 3:19 certainly clarifies what is happening in 22:16. Baptism alone could not be saving Paul or any Israelite, and no other passage would give that idea.

Thanks for asking.
Dr. Mal Couch