Here is a mind-rattling, faith-preserving, heart-warming excerpt from that sermon:
He undertook the office of a Mediator from eternity with delight. He then delighted in the thoughts of saving sinners, and he still delights in it. He never has altered from the disposition to accomplish it. When man actually fell and became a rebel and an enemy, an enemy to his Father and himself; still it was his delight to do the part of a Mediator for him. And when he came into the world, and came to his last agony, when the bitter cup that he was to drink was set before him, and he had an extraordinary view of it, so that the sight of it made “his soul exceeding sorrowful even unto death,” and caused him to “sweat as it were great drops of blood;” still he retained his disposition to do the part of a Mediator for sinners, and delighted in the thoughts of it. So, even when he was enduring the cross, the salvation of sinners was a joy set before him, Heb. 12:2.
I can fathom that in His office as Mediator, Christ never ceases to fulfill His duties. But the fact that He has always delighted in that office and those said duties is incredible. Actually, incredible falls far short; it is beyond comprehension. As Edwards explains this he goes through various stages: Christ delighted to be a Mediator in eternity past; He delighted in it when mankind fell; and He even delighted in it in His life and death. What? Seriously? He delighted in His role as Mediator when He satisfied the wrath and justice of God? He delighted becoming sin for the sinful? He delighted becoming a curse for us? Is Edwards serious? I was riveted as I read this section. And as I was reading the Scripture verse Edwards would use to make his point came into my peripheral vision. Of course! The joy set before Him! The joy set before Him! Hebrews 12:1-2 is as follows, "Therefore, since we are surrounded by so great a cloud of witnesses, let us also lay aside every weight, and sin which clings so closely, and let us run with endurance the race that is set before us, looking to Jesus, the founder and perfecter of our faith, who for the joy that was set before him endured the cross, despising the shame, and is seated at the right hand of the throne of God."
Absolutely astounding! Thank you Jesus!