(((freedomlover))),
That is beautiful. I see Narkissos point, but I am not so sure a phone conversation is the best idea. It is easy to turn around what someone said on the phone—even moments after the conversation is over—but with a letter what you actually said is "recorded" and can be "played back" as many times as he reads it. It would be difficult to imagine a phone conversation affecteing him three years from now, but rereading a letter easily could.
Maybe working in at least one thing for him to look up himself, like, "Even something as simple as looking up the marginal references for Daniel 5:26 raised doubts about the explanations I have always heard."
Respectfully,
AuldSoul