Acts 4:24
And when they heard that, they lifted up their voice to God with one accord, and said, Lord, thou art God, which hast made heaven, and earth, and the sea, and all that in them is: And when they heard that, they lifted up their voice to God with one accord, and said, Lord, thou art God, which hast made heaven, and earth, and the sea, and all that in them is:
After Peter and John were released from prison and reported their examination, the believers responded with great joy. With one accord they lifted their voice together to God in faith, so that their united hearts and faith presented their petitions before Him as the prayer of one person. They addressed Him as the Maker of heaven and earth and sea and everything in them, recognizing His power over all creation.
They prayed while facing threats and opposition to preaching about Jesus, the same determined opposition Christ had met on earth. They sought not to glorify themselves but to exalt Jesus and to rescue souls through His saving message. In that crisis they asked for boldness and courage to speak, and for greater strength to be imparted to them for ministry. They also asked for healing and for signs to be done in the name of Jesus.
Their united prayer was answered at once when the place where they were assembled was shaken and they were filled with the Holy Spirit. They went forth speaking the Word of God with convincing power, so that large numbers were added to the church daily and thousands were converted in a day. God hears and answers such united prayer, while self-seeking, division, jealousy, criticism, and confusion weaken unity and prayer.