He is the Tarot guy who reminds us that we don’t have to answer the phone or the door, that we don’t have to be part of what’s going on around us at all.
We can just sleep through it. Don’t join in, don’t react to rudeness. He also means to stay or remain, to just be and let be.
He is resting up, convalescing, taking time out or even retiring from something.
He is on a vision quest in the Rider Waite illustration here.
It’s part of the knighthood ceremony – which tells you this card is of more recent origin than some others.