Andrea, I agree with you on the border and for a couple of additional reasons that you might keep in mind for future paintings. I think the border's placement is crowding the head too closely. It is creating an Escher-like illusion - that is, it appears to be in front of the boy on the top and left sides, but behind him on our right. This is happening mainly because of the sharp edges and the high contrast.
I love the idea of borders - some of the most successful I have seen include Paul McCormack's
Karen and quite a number of Daniel Greene's images
http://www.portraitartist.com/halloffame/greene.htm . Borders are, at least to me, fascinating - they can be such strong compositional elements and can solve a number of spacial challenges. Actually this makes me think we should start a compositional thread on the use of borders....
I love the concept of the Hebrew lettering! I don't feel, though, that it works where it's placed as well as it might if used in some alternative way. Have you noticed the portraits by karin Wells - where she places the lettering almost as if it's inscribed on the wall behind the subject? Here's a link to one of her paintings:
http://www.portraitartist.com/wells/zabie.htm She also has successfully placed the lettering on a place in front of the subject as in this piece
http://www.portraitartist.com/wells/butterworth.htm
But in either situation, the lettering is clearly subordinated to the subject - in size, value color and edge quality - so that it stays where it needs to, visually. Like anything else, it's also a purposeful part of the overall composition.
You could likewise think about incorporating your lettering in similar ways. Last, you might check the drawing of the yarmulke - the outer edge on our left may be cut too close - if the drawing look right, you can probably solve this one easily with a softer edge.