(Chapter 47, Verse 31) And he said to him, swear to me. And he swore to him: and Israel worshipped against the top of his staff. And in this place, some falsely simulate that Jacob worshipped the top of Joseph's scepter, because he honored his son and worshipped his power, when in Hebrew it is read very differently: And Israel worshipped, he said, at the head of the bed: which means, after his son had sworn to him confidently about the request he had made, he worshipped God against the head of his bed. Indeed, as a holy and devoted man dedicated to God, oppressed by old age, he had his bed positioned in such a way that he himself, in the posture of one lying down, was ready for prayer without any difficulty.
[AD 420] Jerome on Genesis 47:31