Today the first Jesse Tree reading was Genesis 22:1-2, 9-13 - the story of Abraham being told to sacrifice his only son, Isaac. It's a reading that has always bothered me - why would God ask such a thing? Why would God test someone in that way?
The second reading (John 3:16-17) shows us that God allowed his own son to be sacrificed, in a way he didn't ultimately demand from Abraham.
I see the connection. It doesn't make the "why" of either situation any easier to understand. But, I do see the connection.