Jack,

There are several reasons and they give us a window into the profound love of Christ.

1. First, Jesus is quoting Psalm 22, which not only is associated with a righteous suffering servant of God, but is Messianic, for at the climax of the psalm, there is vindication and restoration for the humble servant.
   
   Anyone in earshot of Jesus who knew the Psalms must have had a lump in their throat if they realized what they were hearing was the fulfillment of the Scriptures.
   
   
2. Secondly, Jesus' experience of suffering was so deep He was willing to take all the anguish that we know or could know. He felt what it was like to be in total desolation, apart from God, the chief effect of sin . . . though He sinned not.

Peace,

Bob Kirby