After many days the word of the Lord came to Elijah, in the third year, saying, “Go, show yourself to Ahab, and I will send rain upon the earth.”…And he bowed himself down on the earth and put his face between his knees.
1 Kings 18:1, 42 ESV
God says He will send rain, but Elijah prays for it until he knows it is happening.
I have encouraged you many times to basically “let go and let God” from the perspective of relying on God and not relying on self. This picture of Elijah praying when he was told it would rain is a picture of when we don’t just “let go and let God.” There is work to be done.
We don’t say let go and let God thinking that if God’s sovereign and it’s just going to be a certain way, why does it matter what I do? It matters because that’s how God brings things about. He uses evangelism to bring people into the kingdom and teaching to mature believers into the full stature of Christ, etc. Here, Elijah prays when He already knows it will be. God uses his prayer to bring the rain.
And that’s why we pray for things promised. That’s why we diligently share the gospel to those who will be saved. He chose to partner with our faith in action to carry out His purposes.