"No good thing will He withhold from those who walk uprightly."
God will not lead you into unrealistic thinking. . . .
I didn't say the Lord wouldn't challenge you to do what seems impossible to you. I said He wouldn't lead you into something that was unrealistic.
The "impossible goals" that the Lord lays before us are goals that are in keeping with the talents and abilities He has given us. They are things that we cannot achieve apart from the use of our faith. There is a dimension to these goals that is God's realm. Only He can cause all the pieces to fall into place. Only He can cause the seeds of time, effort, and skill associated with the goal to come to full fruition.
Source: "God's Way Day by Day"