Restoring Faith After a Challenge to It

[Zazzy]

Having never had a god-belief, I'm very interested in how theists overcome challenges to their faith. I was reading this great poem by the incomparable Gerard Manley Hopkins (Irish monk poet, late 19th century):

Thou art indeed just, Lord, if I contend
With thee; but, sir, so what I plead is just.
Why do sinners’ ways prosper? and why must
Disappointment all I endeavour end?
Wert thou my enemy, O thou my friend,
How wouldst thou worse, I wonder, than thou dost
Defeat, thwart me? Oh, the sots and thralls of lust
Do in spare hours more thrive than I that spend,
Sir, life upon thy cause. See, banks and brakes
Now, leavèd how thick! lacèd they are again
With fretty chervil, look, and fresh wind shakes
Them; birds build – but not I build; no, but strain,
Time’s eunuch, and not breed one work that wakes.
Mine, O thou lord of life, send my roots rain.

and I felt very sad at his obvious pain and struggle with a faith that was really important to him (he only wrote about his God).

I really want to hear about problems with faith that were overcome and faith was restored, not about challenges that resulted in permanent loss of faith (although I imagine the former theists here might have had such challenges and had faith restored prior to becoming atheists).

Particularly: what was the problem? What challenged your faith? How did you resolve it and restore faith? Was there a difference in your faith after the resolved challenge?

I'd like to politely request that this stay on topic for at least a while, since I genuinely want to hear these stories.