58 L&N 67.121 has “to extend time unduly, with the implication of lack of decision—‘to wait, to delay.’ νῦν τί μέλλεις … ἀναστὰς βάπτισαι ‘what are you waiting for? Get up and be baptized’ Ac 22:16.”
59 Grk “getting up.” The participle ἀναστάς (anastas) is an adverbial participle of attendant circumstance and has been translated as a finite verb.
60 The expression have your sins washed away means “have your sins purified” (the washing is figurative).
61 The expression calling on his name describes the confession of the believer: Acts 2:17–38, esp. v. 38; Rom 10:12–13; 1 Cor 1:2.

In other versions

And now why do you wait? Rise and be baptized and wash away your sins, calling on his name.’

And now what are you waiting for? Get up, be baptized and wash your sins away, calling on his name.’

And now, why are you delaying? Get up and be baptized, and wash away your sins, calling on his name.’

What are you waiting for? Get up and be baptized. Have your sins washed away by calling on the name of the Lord.’

And now why are you delaying? Get up, be baptized, and wash away your sins, calling on his name!’

And now why tarriest thou? arise, and be baptized, and wash away thy sins, calling on the name of the Lord.

Public Domain