Waiting on someone else and that person's timing is not part of our human nature. We live in time and want things to happen in accordance with our view of the right timing. God, on the other hand, lives outside time and, because of that, He can see when the perfect timing is for every event. And He generally doesn't tell us why the best timing is best. As a result, it is often difficult to wait for God to do things when He knows is best.
Waiting on God is hard. Why?
Because He is outside time, God's timing is usually not the same as ours. For example, Israel had been praying for the Messiah to come for years before He did. As Galatians 4:4 says, "But when the fullness of time had come, God sent forth his Son …" Looking back on events, we can see how the time of Jesus' coming was better when He did come than at any time beforehand—how widespread the Greek language was, the peacefulness in the Roman Empire, the relative ease of travel because of the Roman roads, etc. But man could not see this previously, and waiting was difficult.
As a matter of fact, it could be argued that waiting on God is not just difficult, it is impossible in our own strength. But the benefits gained by waiting on God are tremendous. Isaiah 40:31 says, "but they who wait for the Lord shall renew their strength; they shall mount up with wings like eagles; they shall run and not be weary; they shall walk and not faint." Waiting on God results in us being strengthened. Philippians 4:6–7 says, "do not be anxious about anything, but in everything by prayer and supplication with thanksgiving let your requests be made known to God. And the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus." Rather than worrying about things, we can put all our concerns in God's hand and wait on Him. Then we will experience His peace, which passes all understanding.
This is because of His sovereignty, which is His total control over all creation and circumstance at every time. When we rest in the assurance of His sovereignty, we don't have to be concerned about how things are going to happen and turn out. As Paul said in Romans 8:28, "And we know that for those who love God all things work together for good, for those who are called according to his purpose." Christians can wait on the Lord in the assurance that He will work things out for our good.
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Truth about the Christian Life