One of the great messages repeated throughout the Bible is that prayer can change things. Quite often we as children of God forget that we must pray to receive God's blessings and promises. An example of this would be the children of Israel in Egypt. Exodus 1:8 tells us that a new king arose over Egypt which did not know Joseph.
This new king set taskmasters over the children of Israel and afflicted them, but there was no deliverance. The Egyptians made the children of Israel serve with rigor, and there was no deliverance. Pharaoh told the midwives to kill every son that was born. God blessed the midwives because they saved the children, but still there was no deliverance. Pharaoh charged the people to cast every son of the Israelites into the water, but still there was no deliverance. Moses was born and raised in Pharaoh's house, and still there was no deliverance. Israel was in bondage throughout the whole life of this Pharaoh, but when Pharaoh dies and the children of Israel start to cry unto God (praying), then God hears, remembers His covenant, has respect unto them, and deliverance is set in motion (Exodus 2:23-25).
There are promises of God that we must act on in order to receive the benefit of the promise. Salvation is another example. Even though Jesus died for the whole world and purchased salvation, we must respond to the Lord and act on His Word in order to be a partaker of that salvation. We must repent, be baptized in the name of Jesus, and receive the Holy Ghost.
We have the promise of revival and the power of the Holy Ghost, but in order for those promises to manifest in our lives, we must pray. Prayer does many things. It changes our attitude about the situation. Prayer changes the situation by changing others' hearts. Prayer gets the Lord's attention and causes the Lord to act. Prayer caused God to send an angel and deliver Peter from prison (Acts 12:5-11). Prayer caused Paul and Silas to be delivered from the prison in Philippi (Acts 16:25-28). Prayer enables us to find God because He said that we would find Him if we seek Him with all our hearts (Jeremiah 29:13).
Let's believe the Word of God and continue to pray for the Lord to pour out His Spirit in our lives and for the revival that His Word promises.