What would you expect to happen if God called you to become a pastor and led you to a certain church so that you could feed His sheep? Well, I can tell you from my own experience and from the reported experiences of many of my friends in ministry that you would expect to see some fruit from your labor. After all, most pastors have to sacrifice a lot to follow this call of God: we go to school long enough to be doctors and yet we accept pitifully low salaries in proportion to our education level, and we often move great distances away from our families. Not only that, but we also put in long hours of work that is both mentally and spiritually taxing. So it is natural to expect to see some kind of results. Why then does God so often start us out with heartbreaking failure? That's the question that Moses asked after his first encounter with Pharaoh in Egypt: "O Yahweh, why have you done evil to this people? Why did you ever send me? For since I came to Pharaoh to speak in your name, he has done evil to this people, and you have not delivered your people at all" (Exodus 5:22-23).
Can we say that our response would have been different if we were in his shoes? Moses left the land of Egypt as a murderer running for his life. He had settled into a very happy, comfortable, and prosperous way of life out in the wilderness of Midian. He had no desire to come back to Egypt and do the kinds of things that God was asking him to do, and yet he finally surrendered to God and set his whole life on this course to do God's will. God had even appeared to him and spoke audibly to him telling him that this was his calling and purpose: to tell Pharaoh to let God's people go. So we understand Moses' frustration when he does what is required and things get worse for everybody. Pharaoh just dismisses him, absolutely refusing his demand, and then the Israelites get smashed with extra work just because Moses came, leading pretty much everyone to hate Moses.
A lot of pastors have a similar experience. We come out to these churches that God has called us to and we seek to do what He has commanded us: we preach His Word. But what we expect to happen doesn't happen. We have read Isaiah 55:11 that says that God's Word will not return void, but what we find is that people start leaving. It turns out that a lot of people don't want to be taught the Word. So Moses' complaint becomes our own: "Why did you ever send me?" "I was happy where I was! I didn't need this!" What are we missing here?
What we're missing is the glory of God. Moses forgot that God told him that "the king of Egypt will not let you go unless compelled by a mighty hand" (Exodus 3:19). What we're missing is that if Moses would have stalked right up to Pharaoh as soon as he arrived, demanded that the Israelites be freed, and then got what he asked for, it would have looked as if Moses had the mighty hand to compel Pharaoh. He would have been the hero of the people. As it was, Moses' strength and aptitude (small though this was) had to decrease so that God's glory and the display of His power could increase. God doesn't need to throw ten miraculous plagues and shine forth His glory if His human servant can accomplish it all with a short speech.
And so why should we as pastors expect any different. If we were to walk into a struggling church, preach a few Sundays, and then all of a sudden start to see amazing growth, everyone - including us - would think that we had something to do with it. God desires to get us to the place where it is obvious to everybody that He is the Great One that deserves all the praise. He hasn't called us in vain; He's just waiting to give the fruit until it is obvious that it could have come from no other source. To God be the glory!