“I’ve had several opportunities to renounce my faith in the past 20 years...”
I imagine very few Believers don’t have times when they doubt God, lack faith, etc. “Blessed are those who are poor in spirit, for they will inherit the Kingdom of God”.
I read on FR quite awhile ago where they found some letters of Mother Theresa, and how they showed all sorts of fears and lack of faith. I suppose that is sort of like that definition of “courage”. Courage is just doing want needs to be done in spite of being scared.
OTOH, I might put him in touch with a former pastor of ours that came new to our church. About a year in he gave a sermon on how Jesus was NOT born of a Virgin, “I grew up on a farm, that’s impossible”. We had him over for dinner shortly after that. I asked him “Well, I’m afraid I already know what you think about the Resurrection.” He of course didn’t believe that either! We told him to take us off the rolls as we wouldn’t be back. And take the choir books with you.
What you say is very true of Mother Theresa having doubts. The same was true of every single apostle, disciple, or saint. You can’t approach the dark-night-of-the-soul without having doubts, and you can’t experience God without going through the dark-night-of-the-soul.
The process though is not doubting God, it is doubting “self” and the realization that we are not in control, a necessary step in surrendering to God and finding joy.
There are no atheists in foxholes!