is the sheer strength of his character. After he was lied to and felt betrayed by his mentor and after going for hajj and seeing that the religion he’d been putting his faith in was basically a fabrication, he didn’t stop or give up the whole idea but rather readjusted his view points and just soldiered on working for what he considered the most important thing since the very beginning; freedom.
I’ll venture to say that most people would’ve given up the whole faith after discovering the extent they had been mislead but Malcolm X didn’t stop his former experience to hinder him from seeing the beauty of religion free from the taint of racism when he went to Makkah. When he got back to America, he didn’t shy away from the fact that they’d been mislead but rather continued working for the one thing that he believed in above all the inter-fighting that started taking place. That takes a hell lot of guts.
He never even lashed out at Elijah Mohammed, he just tried to keep the black community together to continue fighting for their collective freedom, regardless of whatever feelings he might’ve had about his former mentor. That takes a hell lot of character.