God worked through the apostles with miracles of healing and judgment, and used them both as mercy and as advertisement for the church. Many signs and wonders were done through their hands, so that people carried the sick into the streets so that Peter's shadow might fall on them. Crowds from the surrounding cities brought the sick and those tormented by unclean spirits to Jerusalem, and all were healed. These healings overcame the people's dread of the apostles, so that believers were added in multitudes. Peter also held a penetrating gift of insight into hidden intentions. He exposed the deceit of Ananias and Sapphira, who lied about the price of their land to gain acclaim for a sacrifice they had not made. Their sin was a lie against the Holy Spirit and against God, not merely men. God Himself executed them, as a parallel to Achan in Israel's early history, to establish respect for Him and His government at the church's beginning. Angelic intervention also marked the apostles' work: an angel opened the prison doors at night and commanded them to stand and speak boldly in the temple. The guards found the prison securely shut with no one inside, which left the Sanhedrin perplexed and wary of the apostles' influence with the people.

The healing of the lame man at the Beautiful Gate shows the continuing power of the risen Christ working through others, in the same pattern as Jesus' own ministry: a healing, conflict with the leaders, preaching, and a standoff. The man was a well-known fixture, lame from birth and about forty years old, so the evidence could not be argued away as the tongues and wind of Pentecost might have been. Peter had no silver or gold, but he gave what he had, acting in the name of Jesus Christ of Nazareth, and the healing was instantaneous, fulfilling Isaiah 35:6. The priority is clear: social help is not wrong, but it ranks below the spiritual work of preaching the gospel. The crowd's wonder was not faith, since being impressed by the spectacular is not trust in God, as Israel's experience in the wilderness showed. Peter immediately corrected any notion that the power lay in himself and John, whether through their own power or godliness. The power is in the name of Jesus, and it becomes effective through faith in that name, a faith that itself comes through Jesus. Such faith rests on hearing the gospel preached, and it is evidenced by obedience, prayer, study, and growth. God worked the miracle to focus attention on this point and to lead the people to repent, believe in the risen Christ, and receive forgiveness.

The apostles' miracles, such as Peter's healing of the lame man at the Beautiful Gate, followed the pattern of Jesus: a miracle, usually a healing, followed by effective preaching. Together with the preaching, these miracles provoked the persecution of the church. The Sadducees, who denied the resurrection and rejected the idea of a personal Messiah, felt their position threatened and could not deny the healing. They admitted that a notable miracle had been done, evident to all in Jerusalem, yet their minds stayed closed by their desire to protect their vested interests, so they simply tried to silence the apostles. Peter turned the healing into a gospel message by using the Greek word soteria, which covers deliverance from sickness and from mortality to immortality, so that "made well" led to salvation in no other name than Jesus Christ. The name carries no superstitious power; the healing proves that Jesus is alive and answered prayer. The apostles' bold speech was the fulfillment of Jesus' promise that the Holy Spirit would give them words their adversaries could not resist. The church then prayed not for the removal of the threats but for boldness and for God to stretch out His hand to heal, so that signs and wonders would be done through Jesus' name and promote the preaching. God answered by shaking the place and filling them with the Holy Spirit. Great power accompanied the apostles' witness to the resurrection. The sudden deaths of Ananias and Sapphira, executed by God, showed the church that He meant business and that honesty is the foundation of the community.

The apostles' miracles are works of dunamis, the Greek word for power that is also translated "mighty works," "wonderful works," and "miracles." These are accomplishments typically beyond normal human capability, performed by God through others such as the apostles (Mark 9:39; Acts 6:8; 19:11; II Corinthians 12:12), just as they were done through Jesus Christ (Acts 10:38). The power is God's, not the apostles' own. Even when Christ performed miracles, the Father actually did the work (John 14:10), and Christ was His chosen vessel. The source of this power is the Holy Spirit. Christ told the disciples, "You shall receive power when the Holy Spirit has come upon you" (Acts 1:8), and once set in motion, this power keeps working in their lives essentially without their governing it. Dunamis is morally neutral, since it can serve God or Satan, but the apostles' miracles show it used for God's purposes. God delegates whatever power is needed for what He has ordained, sometimes through natural ability and sometimes through added miraculous power. Dramatic works such as healing by a passing shadow or moving mountains are not given to every believer, and the lack of them is no mark of unfaithfulness. Faithfulness with the measure given matters most.

Jesus gave the Twelve power over unclean spirits and authority to heal the sick, cleanse lepers, raise the dead, and cast out demons, and He sent them out with a commission to preach that the Kingdom of Heaven is at hand. They received this power before they were converted and before they had God's Spirit, which shows that God alone controls His power and gives it to whomever He wills or withholds it until He wills. A person's ability to work miracles is therefore no measure of righteousness. John the Baptist, whom Jesus called the greatest among those born of women, is never recorded as healing anyone, raising anyone, or doing anything extraordinary beyond preaching. God determines who is healed and who performs miracles, and that decision is His responsibility. The apostles were ordinary men from many different walks of life, chosen and appointed to be with Jesus and then sent forth. Their miracles were not the focus of their calling, since the Bible concentrates on the work they did, and they were to give freely what they had freely received, taking no payment. Miracles will again be done by God's people when He wills.

Martin Collins asserts that miracles and signs from God, while certainly generating awe and fear, seldom lead to righteousness, but more likely to continued rebellion. Jesus points out that only an adulterous generation seeks after miracles and signs. No greater period of miracles took place in history than at the time of the Exodus, including the plagues of Egypt, the parting of the Red Sea, and the giving of the Law at Mount Sinai. Yet, the stiff-necked Israelites rebelled against God on ten separate occasions. The longest period of growth and stability in Israel occurred under David's and Solomon's reigns, a period attended by no miracles. Elijah and Elisha performed godly miracles during a massive apostasy. John the Baptist, proclaimed by Jesus as the greatest of men, performed no miracles whatsoever. The miracles and signs Jesus performed were received with awe, but also with much ridicule and scoffing from the religious leaders. Axiomatically, the spiritually weak need miracles; the more spiritually mature one becomes, the fewer signs and wonders he needs to sustain faith. God blessed the Corinthian congregation with spiritual gifts (of discerning prophecy, speaking in tongues, healing, etc.), but the vanity which these gifts produced led to party-spirit and jealousy. In the future, the False Prophet and Beast will lead many astray by miracles and signs, deceiving most of the world. As God's called-out ones, walking humbly with God should displace any desperate need for signs and wonders.