{Repent therefore} (metano(8873)ate oun). Peter repeats to
this new crowd the command made in  Ac 2:38  which see. God's
purpose and patience call for instant change of attitude on their
part. Their guilt does not shut them out if they will turn. {And
turn again} (kai epistrepsate). Definitely turn to God in
conduct as well as in mind. {That your sins may be blotted out}
(pros to exaliphth(886e)ai hum(936e) tas hamartias). Articular
infinitive (first aorist passive of exaleiph(935c), to wipe out, rub
off, erase, smear out, old verb, but in the N.T. only here and
 Col 2:14 ) with the accusative of general reference and with
pros and the accusative to express purpose. {That so} (hop(9373)
an). Final particle with an and the aorist active subjunctive
elth(9373)in (come) and not "when" as the Authorized Version has
it. Some editors put this clause in verse  20  (Westcott and
Hort, for instance). {Seasons of refreshing} (kairoi
anapsuxe(9373)). The word anapsuxis (from anapsuch(935c), to cool
again or refresh,  2Ti 1:16 ) is a late word (LXX) and occurs
here alone in the N.T. Surely repentance will bring "seasons of
refreshing from the presence of the Lord."