Rewatching the episode and the part where he talks about losing a child is like losing a limb... he seems off in space, lost for a second.
I think he may have lost a child? Perhaps even if its a grown child that is in Canada, was executed for being gay or breaking some other Gilead law, or didn’t agree with his work and disowned him.
Maybe this evoked a change in him? Just a thought. He seemed lost in his thoughts for a second. (These are total speculations and not based on any spoiler.)