Habakkuk was concerned over the spiritual condition of Judah. His response was to pray. God answered his prayer and Habakkuk was dismayed by God's answer. He then registers his complaint and sits upon a wall to wait for God's response to his complaint. Habakkuk gets a response in the form of a vision that he is instructed to write down. The vision was about a future time when God would restore Israel to its rightful place.
No, God was not going to change His mind about sending Judah off into captivity as punishment for their iniquities. The vision given to Habakkuk is again alluded to in Hebrews 10:38 where we get further insight into its details. We learn that the vision given to Habakkuk will have its fulfillment when Jesus Christ returns to set up the Millennial Kingdom. The lesson we need to learn about our prayers and God's answer to them is very simple. Habakkuk prayed that God would deal with Judah's iniquity [Habakkuk 1:2] and restore the nation. God's initial answer provided the first step in the process but the ultimate answer to Habakkuk's prayer would not come for centuries.
In the mean time, Habakkuk and all those followed him were to told to "live by faith" trusting God for the fulfillment of His Word. When we pray that is exactly what God is telling us today. We want God to answer our prayers sooner than later. We become frustrated by what we perceive is inaction, silence or an answer that is totally different in the way or timing we expected from God. What are we to do in such circumstances? We are to live by faith. That means believing God will answer our prayers [faithful]. In answering our prayers He will do what's best [love] in the best way to accomplish the best purpose [wisdom] and that nothing can prevent Him from accomplishing His purposes [sovereign].
When we pray in faith we need to trust God to answer our prayers "In His time and in His way." After you pray, sit back, watch and wait. It not a time for complaining or discouragement for God for "the Lord is in His holy temple, let all the earth keep silence before Him." [Habakkuk 2:20] Remember God is God and He answers prayer. Faith recognizes the truth of "In God's time and in God's way."