I wouldn't worry about it. He's probably lying. An employer can't take action against a person that easily for something they did in their private life. Ignore his guilt trip.
Good for you! First, if he does include professional e-mail, it (to me) counts as work-related. Someone like that deserves all the bad stuff he gets. People should learn that they can't use the internet to spew all their hatred. Besides, he's only probably afraid HE may be potentionally gay. Don't worry about him losing his job. A dick like that must reap the consequences.
OR, just speculating of course, you have snagged the attention of a BAD ju-ju borderline psychotic, who now (since he has been fired and his wife and kids have left him, probably driving him off the edge) has all kinds of free time to look you up.
i bet you're one of those gays.
And so what if they are? People shouldn't be posting shit like that in the first place.