When we reflect on the ways of God, there are two questions that surely you have pondered. Why does God choose to carry out His will on earth through us? is the first. The second: What will we be doing in Heaven? These sound like two totally unrelated questions, yet they are inseperately linked. We can see this as we look to scripture for answers.
In dealing with the first question, lets examine two passages, from the Old and New Testaments:
Gen 25:21- "Now Isaac pleaded with the Lord for his wife, because she was barren; and the Lord granted his plea, and Rebekah his wife conceived."
Matt 9:38- "Therefore pray the Lord of the harvest to send out laborers into His harvest."
In the case of Isaac, we can ask, "Why did he have to pray for his wife to conceive?" After all, did not God promise Isaac's father Abraham that his descendents would be numerous as the stars in the sky and as the sand on the sea? Can we not safely assume that Abraham shared this good news with his son and daughter-in-law? Knowing that God keeps his promises, why would Isaac have to pray at all? We couldn't he just sit back and wait for God to act? Isaac married at age forty, but Rebekah bore no children until he was sixty. Why did he have to wait for so long? Why did he have to pray for Rebekah before God's promise to Abraham could be begun to be fulfilled?
Why did Jesus command us to pray that laborers would be sent into the harvest? After all, we know that it is the will of the Trinitarian God that all be brought to repentance. Jesus is the second person of the Godhead. Why can he not make sure there are enough laboers in the field on His own? Why would the Father, Son and Holy Spirit rely on us to pray for laborers? After all, our track record is nothing to brag about.
There are other examples we could come up with in regard to this matter. Even though Ezra knew he had God's favor, on his way back to Israel from captivity, he and those with him stopped to fast and seek direction. (Ezra 7:6, 8:21-23) Jesus told us to knock and the door will be opened unto us. (Matt 7:7) In the origional Greek, the text reads that not only are we to knock once, but to keep on knocking until the door is opened. Why? Ezra knew the answer. '..."the hand of our God is upon all those for good who seek Him, but His power and His wrath are against all who forsake Him." ' (Ezra 8:22) Not to seek direction from Him, even though Ezra knew he had His favor, would have amounted to forsaking the Lord. He would have been relying on something other than God. In Psalm 145:17-21, David tells us that God hears those who call on him; He rescues those who love Him. Even though we are in possession of God's promises, it is only in the process of seeking Him that we truly learn to rely on Him. Maybe Isaac did not have an heir for twenty years is that he needed that time to learn to seek God in this matter instead of relying passively on God to fulfill His promise. It is by our seeking God actively in all things that we become the "over-comers" that Jesus speaks of in Revelation 3:21 : "To him who overcomes I will grant to sit with Me on My throne, as I also overcame and sat down with my Father on His throne." As Jesus overcame, so must we. We must learn obedience as He did, and His learning took many years. Only in obedience can we overcome Satan and Spirtual forces and be with Him who overcame.
Being overcomers allows us to do in Heaven what God plans for us to do. What will we be doing in Heaven? Revelation 5:10 reveals to us that we will be "...kings and priests to our God; And we shall reign on earth." To reign means that we will rule. What will our reign will be like, I do not know. But I do know that we will have tasks to do in heaven. And our obedience prepares us for those tasks that await us. The undertaking of these tasks is a priviledge for those who seek him. It is a reward. And here we can link the two questions. We learn obedience and reliance on God so that we can be made ready for what God has for us in Heaven. As the writer of Hebrews puts it: "But without faith it is impossible to please Him, for he who comes to God must believe that He is, and that He is a rewarder of those who diligently seek Him." (Heb. 11:6)
(All scripture quotations are from the NKJV.)