It is absolutely essential for people to cooperate with God. There are some who think that God simply decrees what will happen in the world and it happens, but taking biblical texts seriously, we have to see that humans have a responsibility to use their own free will to cooperate. See this passage in Numbers:
Speak to the Israelites and say to them: When you cross the Jordan into the land of Canaan, you will drive out all the inhabitants of the land before you. You will destroy all their carved figures. You will also destroy all their cast images. You will eliminate all their shrines. You will take possession of the land and live in it, because I’ve given the land to you to possess. You will divide up the land by lot according to your clans. To the large you will make its inheritance large, and to the small you will make its inheritance small. To whomever the lot falls, that place will be his. You will inherit land according to your ancestral tribes. But if you don’t drive out the inhabitants of the land before you, then those you allow to remain will prick your eyes and be thorns in your side. They will harass you in the land in which you are living. Then what I intended to do to them, I’ll do to you.
This is God speaking to the Israelites through Moses. This is a reminder that God has promised a certain land to them. Note this well–God promised the land to them, but they have to act on the promise! The Israelites will not simply walk across the Jordan and settle in the land that God has promised to give them; they will have to fight for it and they will have to be faithful to God’s commands to keep it.
God makes promises to us in this day and age as well, promises of salvation, healing, wholeness, and holiness. Yet we have to cooperate with God in order to see those promises realized in our lives. We have to voluntarily allow God to work in us and through us to shape us into who he wants us to be. This means that we will encounter situations in our lives when we have a choice: either obey God or not, either try to take the God-honoring path or not. What choice we make will largely determine how those promises play out in our lives. The more we make God-honoring decisions, the more we will experience salvation, healing, wholeness, and holiness. The more we elect to go our own way, the less we will see these promises in our lives.
The choice is ours. God has promised to give these blessings to us. It is up to us to cooperate with him to receive them.