God will test our faith. The apostle Peter wrote that various trials cause heaviness:
so that the tested genuineness of your faith—more precious than gold that perishes though it is tested by fire—may be found to result in praise and glory and honor at the revelation of Jesus Christ. (1 Peter 1:7)
Solid faith, not faith-leaf—like gold leaf, a thin layer of faith hammered around the outside—solid faith now will result in our being esteemed and rewarded by God when we see Jesus Christ and will no longer need faith.
In the meantime the “various trials” that do this testing are manifold. One could translate the Greek adjective “multi-colored.” The trials come in different shapes and sizes. They also come in different degrees of importance to us.
God tests our faith through national elections, but that doesn’t hit quite as close to home as, say, losing your home. Or if He’s given you a job, you know it was by His grace that you got the job, and now He appears to be taking that job away by requiring you to stand up for righteousness. Or if a child or a spouse gets very sick. Or if the plans you had, plans to be productive and minister for Him, get interrupted. These and more will test your trust in God.
I’ve heard it said, “Put your Isaacs on the altar.” If God wants you to surrender something you think is important, even crucial, for His mission, then You must trust Him that He will bless you as He takes it away. This is a test of faith, a purifying of faith, and a strengthening of faith. We need it. And if we fail a test, we don’t have to wait a certain amount of time before we try again, we just need to repent and turn back to Him in trust.