What does Acts 4:31 mean?

Peter, John, and other leaders of the church are in a room in Jerusalem, praying for the strength to continue preaching the word of God (Acts 4:23–30). "Word" is from the Greek root word logos which means an idea, a doctrine, and/or a message. John 1:1 identifies Jesus as the Word of God. Here, before the New Testament books have been widely spread, the "word of God" does not yet have the commonly-understood meaning of "Scripture." It does mean the total message God means to give mankind. This includes that Jesus is the Son of God, that He is the Savior, that He rose from the dead, and that He is the core of salvation.

Sometimes, the Bible shows us people who are praying for things they already know God wants. Daniel counted the years until it was time for God to restore Jerusalem and then prayed that God would make it happen (Daniel 9:2, 16–19). In Jesus' "High Priestly Prayer," Jesus asks God to guard the testimony of His followers—which was God's plan all along (John 17:15). In the same way, the leaders of the church in Jerusalem pray for the boldness to speak God's word and the signs to validate that teaching (Acts 4:29–30).

If they know this is God's will, why do they pray for it? Praying for God's will shows that we are ready to submit to His plan. It prepares our hearts for the changes about to happen. It is a way of stepping forward to volunteer for His work. It is good to have a demeanor that is properly submissive to God. To state that willingness in words for a specific goal at a specific time is powerful.

The Holy Spirit honors their request by making Himself evident in their midst. They have chosen a path of hardships, persecution, and martyrdom. The Holy Spirit will never abandon them, and He will continue to strengthen them until their work is finished. Later, when faced with danger, they will be able to look back at this moment and remember both their willingness and the assurance that God approved of their prayer.