A: Well, the best thing you can do to keep your sons pure is to respect and love their mother. And that's, quite honestly, 80% of it. The remaining 20% is to teach them discipline and self-control when they're 2.
When your son hears about a poor kid growing up without a dad, does that turn his stomach? Dads running off and leaving mom to pick up the pieces - that should really upset your sons. You should teach them that this is not noble; this is not chivalric; this is not what God calls us to. And if you're modeling that in the home, they will pick up on it naturally.
The 2nd thing is that boys are creatures of appetite. They are driven by their passions, by their hunger, by competition, that sort of thing. So you need to teach them to be disciplined and self-controlled when they're 2 and 3 and 4 years old with regard to these relatively simple appetites. If you don't teach them self control in all these simple appetites, and they get to be 12 or 13, and all the sudden the mother-of-all-appetites overwhelms them ... you tell me how they're going to feel?
If discipline is a novel concept, the last time you want to learn it is when your body has just flooded with testosterone. Fathers teaching their sons how to compete in sports without loosing their temper, how to be patient at the dinner table without demanding things from their mother, how to get up and make the bed in the morning - every form of discipline that's in a context of love that young boys get is going to be an aid to resisting sexual temptation.
-Douglas Wilson in an interview on St. Anne's Pub