Prayer aligns your life with God so that He chooses to demonstrate His power through you.
The fervent prayer of the people at Pentecost did not induce the Holy Spirit to come upon them. Prayer brought them to a place where they were ready to participate in the mighty work God had already planned.*
When the day of Pentecost had fully come, they were all with one accord in one place (Acts 2:1).
Henry T. Blackaby and Richard Blackaby, Experiencing God Day-By-Day, p. 257.