John 2:19

But why doth He both there, and here, and everywhere, give this for a sign, at one time saying, "When ye have lifted up the Son of Man, then ye shall know that I Am"; at another, "There shall no sign be given you but the sign of the prophet Jonas"; and again in this place, "In three days I will raise it up"? Because what especially showed that He was not a mere man, was His being able to set up a trophy of victory over death, and so quickly to abolish His long enduring tyranny, and conclude that difficult war. Wherefore He saith, "Then ye shall know." "Then." When? When after My Resurrection I shall draw (all) the world to Me, then ye shall know that I did these things as God, and Very Son of God, avenging the insult offered to My Father.

Of Adam then is Christ's flesh: of Adam the temple which the Jews destroyed, and the Lord raised up in three days. For He raised His own flesh: see, that He was thus God equal with the Father. My brethren, the apostle says, "Who raised Him from the dead." Of whom says he this? Of the Father. "He became," saith he, "obedient unto death, even the death of the cross; wherefore also God raised Him from the dead, and gave Him a name which is above every name." He who was raised and exalted is the Lord. Who raised Him? The Father, to whom He said in the psalms, "Raise me up and I will requite them." Hence, the Father raised Him up. Did He not raise Himself? And doeth the Father anything without the Word? What doeth the Father without His only One? For, hear that He also was God. "Destroy this temple, and in three days I will raise it up." Did He say, Destroy the temple, which in three days the Father will raise up? But as when the Father raiseth, the Son also raiseth; so when the Son raiseth, the Father also raiseth: because the Son has said, "I and the Father are one."

He does not however provoke them to commit murder, by saying, Destroy; but only shows that their intentions were not hidden from Him. Let the Arians observe how our Lord, as the destroyer of death, says, I will raise it up; that is to say, by My own power.

And what say they? "What sign showest Thou unto us, seeing that Thou doest these things?" Alas for their utter madness! Was there need of a sign before they could cease their evil doings, and free the house of God from such dishonor? and was it not the greatest sign of His Excellence that He had gotten such zeal for that House? In fact, the well-disposed were distinguished by this very thing. At one time then He said, that the Temple was made by them "a den of thieves," showing that what they sold was gotten by theft, and rapine, and covetousness, and that they were rich through other men's calamities; at another, "a house of merchandise," pointing to their shameless traffickings. "But wherefore did He this?" Since he was about to heal on the Sabbath day, and to do many such things which were thought by them transgressions of the Law in order that He might not seem to do this as though He had come to be some rival God and opponent of His Father, He takes occasion hence to correct any such suspicion of theirs.

Wherefore He will not give them a sign; and before, when they came and asked Him, He made them the same answer, "A wicked and adulterous generation seeketh after a sign; and there shall no sign be given unto it, but the sign of the prophet Jonas." Only then the answer was clear, now it is more ambiguous. This He doth on account of their extreme insensibility; for He who prevented them without their asking, and gave them signs, would never when they asked have turned away from them, had He not seen that their minds were wicked and false, and their intention treacherous. Think how full of wickedness the question itself was at the outset. When they ought to have applauded Him for His earnestness and zeal, when they ought to have been astonished that He cared so greatly for the House, they reproach Him, saying, that it was lawful to traffic, and unlawful for any to stop their traffic, except he should show them a sign. What saith Christ? "Destroy this Temple, and in three days I will raise it up." Many such sayings He utters which were not intelligible to His immediate hearers, but which were to be so to those that should come after. And wherefore doth He this? In order that when the accomplishment of His prediction should have come to pass, He might be seen to have foreknown from the beginning what was to follow; which indeed was the case with this prophecy.