In a similar pattern as was seen in Jesus’ ministry, Peter and John use miracles to confirm what they are preaching is from God. The man who was healed would have been seen by everyone entering the temple over a period of many years. His physical limitations would have been known to all. The man does not go through a slow process of healing and building up muscles, but immediately begins to leap. This makes Peter’s audience much more open to hearing what he has to say. Peter is careful to make sure everyone knows what he is doing is in the name of Jesus.
God still does miracles today. Sometimes it is healing some type of physical problem. At other times it is turning someone’s life around. When he does this, it is important that we recognize and tell others it was done in the name of Jesus. Obviously the healing benefits the person who is healed, but the greater healing is spiritual; their sins are forgiven and they spend all of eternity with God!