Demonstrate by your lives that you have [really] repented, and quit saying to yourselves, 'We claim Abraham as our forefather,' because I tell you, God is able to make Abraham's children out of these stones. And even now the axe is also ready to chop down the trees at their roots [i.e., you Jews]. Every tree [i.e., person] that does not produce wholesome fruit [i.e., a godly life] will be cut down and thrown into the fire [i.e., the punishment of hell]." Then the crowds asked him, "What then must we do [i.e., to demonstrate our repentance]?" read more.
And he answered them, "The person who has two coats should give [one of them] to the person who does not have any; and the person who has food should do the same thing." Then some tax collectors came to him to be immersed and asked him, "Teacher, what must we do [i.e., to demonstrate our repentance]?" And he answered them, "Do not collect any more [tax money] than you are required to." Some soldiers on duty also asked him, "And what must we do [i.e., to demonstrate our repentance]?" And he answered them, "Do not force people to give you money or accuse them falsely, and be content with your pay."

Now when the people heard this message [of Peter and the other apostles, See verse 14], they were convicted [of its truth] in their hearts and said to Peter and the other apostles, "Brothers, what shall we do [about our condemned condition]?" And Peter replied, "Every one of you must repent [i.e., change your hearts and lives] and be immersed in the name of Jesus Christ [i.e., by His authority] so that your sins will be forgiven [by God] and then you will receive the gift of the Holy Spirit [to live in your hearts].