Shackleton was an amazing man, but from what I have read he did not really give credit to Providence who saved him and his crew.
And how utterly ridiculous that he survived the harrowing journey and rescue, only to return to sea!! Dude, when you narrowly escape death, does it make sense to return to the same circumstances?? He died of a heart attack on his second journey aboard ship.
Idiot.
It's just a hunch, but one can always tell an armchair quarterback...