You will have no problem believing in that. He listened to Paul as he was speaking. Paul looked directly at him, saw that he had faith to be healed. . . This man's faith was given to him. That the person has been regenerated.
Faith proceeds from that divine act of regeneration.
Regeneration precedes faith. At that, the man jumped up and began to walk. We too are only men, human like you. They were just men, instruments chosen by God to bring the good news in which these people would believe and be saved. And as we read further, we see that the mood of the crowd changed from adulation to antagonism toward the apostles.