In this verse Joseph removes the two boys from Jacob and bows to the ground. From this it would appear that the blessing has been completed and Joseph bows to give thanks to his father and to God. However, according to the text as we have it, the blessing (verses 15-16) has not yet been pronounced.

Then Joseph removed them from his knees: in the Hebrew text Joseph does not place his sons on Jacob’s knees in verse 10. Whatever took place, it appears in this verse that the boys are on his knees (Good News Translation on “his lap”). The important point is that, by taking them on his knees, Jacob is recognizing Joseph’s sons as his own by adoption. See 30.3. Westermann says the Hebrew expression need not mean that the boys were literally sitting on Jacob’s knees. Driver translates the expression “from between his knees.” Some interpreters understand this expression to be an idiom meaning “from his lap.” See Good News Translation and others. See also the comments in this Handbook at 30.3.

He bowed himself with his face to the earth: see 18.2 and 19.1.

Quoted with permission from Reyburn, William D. and Fry, Euan McG. A Handbook on Genesis. (UBS Helps for Translators). New York: UBS, 1997. For this and other handbooks for translators see here .