What?!?! Someone please help!!!

I started reading "The Pleasures of God", by John Piper, last night as I was travelling from Champaign to Chicago to Seattle. Good stuff, I have to say.

But then I stumbled upon something which caught me off guard. In trying to explain how God has been perfectly content and exuberantly happy with Himself and His own Godhead Trinity since before the creation of time and all worlds, Piper calls upon the writing of Jonathan Edwards ("An Essay on the Trinity") to help explain this point:

If a man could have an absolutely perfect idea of all that pass'd in his mind, all the series of ideas and exercies in every respect perfect as to order, degree, circumstance etc. for any particular space of time past, suppose the last hour, he would really, to all intents and purpose, be over again what he was that last hour. And if it were possible for a man by reflection perfectly to contemplate all that is in his own mind in a hour, as it is and at the same time that it is here, in its first and direct exitstence; if a man, that is, had a perfect reflex or contemplative idea of every exercise at and during the same time that that exercise was, and so through a whole hour, a man would really be two during that time, he would be indeed double, he would be twice at once. The idea he has of himself would be himself again.

Therfore as God with perfect clearness, fullness and strength, understands Himself, views his own essence (in which there is no distinction of substance and act but which is wholly substance and wholly act), that idea which God hath of Himself is absolutely Himself. This representation of the Divine nature and essence is the Divine nature and essence again: so that by God's thinking of the deity, [deity] must certainly be generated.

Hereby there is another person begotten, there is another infinite eternal almightly and most holy and the same God, the very same divine nature. And this person is the second person of the Trinity, the only begotten and dearly beloved Son of God; He is the eternal, neceessary, perfect, substantial and personal idea which God hath of Himself; and that it is so seems to me to be abundantly confirmed by the word of God.

What?!

Jesus is the essence of God's perfect understanding of Himself?! Can someone please help me understand how this is biblical and not just philosophical musings?!

It was just a footnote in Piper's book, so the biblical references (which so "abundantly confirm" Edwards's stance) are not given in support of this idea. Someone please help! I've never heard this idea put forth before, and would like to know more about it.