You can easily tell whether someone is walking in faith or in unbelief when they are pressed by time. When pressure builds after an expected process has refused to yield the desired result and you begin to wonder whether or not you heard God right, that’s unbelief, not faith. Many people unknowingly walk in unbelief every day because they do not fully understand what it means to be unbelieving. To be unbelieving is to doubt the integrity of God’s word.
Romans 4:19-21 says “Without weakening in his faith, he faced the fact that his body was as good as dead- since he was about a hundred years old – and that Sarah’s womb was also dead. Yet he did not waver through unbelief regarding the promise of God, but was strengthened in his faith and gave glory to God, being fully persuaded that God had power to do what he had promised.” (NIV)
Faith does not doubt no matter the circumstances. Abraham did not doubt because his time for having a child had passed; he was strengthened in his faith that God was going to do what He had promised. Time was testing his faith, but he did not waver. Faith is fully persuaded that what God has said is the absolute reality.
Where unbelief starts fretting because of some delay, faith remains unshaken because it does not consider or think of the process; rather, it focuses on results. God promised the Israelites that He was going to take them out of Egypt to the Promised Land. Though it took them forty years to reach Canaan, God fulfilled His promise. Those who doubted along the way did not make it to the Promised Land. This means that for you to get what God has promised you, you need to have faith.
You should not complain about the time it takes, but be thankful and give glory unto God that one day you will testify the goodness of the Lord in your life.