A great article, written as a dialogue, can be found on John Piper’s Desiring God website. Here’s a sample of the conversation the article contains:
Prayerless: I understand that you believe in the providence of
God. Is that right?
Prayerful: Yes.
Prayerless: Does that mean you believe, like the Heidelberg
Catechism says, that nothing comes about by chance but only by
God’s design and plan?
Prayerful: Yes, I believe that’s what the Bible teaches.
Prayerless: Then why do you pray?
Prayerful: I don’t see the problem. Why shouldn’t we pray?
Prayerless: Well, if God ordains and controls everything, then
what he plans from of old will come to pass, right?
Prayerful: Yes.
Prayerless: So it’s going to come to pass whether you pray or
not, right.
Prayerful: That depends on whether God ordained for it to come
to pass in answer to prayer. If God predestined that something
happen in answer to prayer, it won’t happen without prayer.
Prayerless: Wait a minute, this is confusing. Are you saying
that every answer to prayer is predestined or not?
