The thing about promises is that unlike a contract or a covenant, they’re always one-way. So when the teacher he follows tells him to leave, he makes a promise that he wouldn’t, not because he hated being alone, but because his teacher has been alone for far too long.
So when all the prophets around them keep reminding him that his teacher will be the one leaving first, he tells them to stop. It’s a painful, nagging feeling, one he’d rather forget, even if he has nothing left to learn or lose.
His teacher writes his will, and so he asks for an inheritance that’s almost impossible to increase the chances of his teacher staying.
The separation happens anyway, and in that moment, something more than a garment was torn in half, and nothing was put back together.