It can definitely happen, but you just went through a divorce, so I'm guessing you're not ready yet. Give yourself time to recover, and let him know you need that too. Give him a timeframe to know when he can bring it back up, but you can bring it up sooner if you choose. You need to adjust to your new life before adding a relationship to it. If you choose to try it, take it slow, and you may be able to go back to friends if it doesn't work.
I'm guessing he has liked you for a while, if he's already mentioned "interest in changing the direction of your relationship." I'm guessing he wants to give you time to recover, but he also doesn't want to lose his chance with you. He's conflicted, so he's mentioning it now.