John 13:30

The Savior said to Judas, "What you are going to do, do quickly," and for once the betrayer obeys the teacher. For when he had received the morsel, he neither hesitated nor procrastinated, but as it is written, "he went out immediately" to do quickly the work of betrayal in accordance with Jesus' command. And "he went out" truly, for he not only went out of the house in which the supper was held, according to the simpler meaning, but he also went out from Jesus in a final sense, analogous to the statement "they went out from us."

"And it was night," has not been interjected in vain by the Evangelist. The perceptible night at that time was symbolic, being an image of the night that was in Judas's soul when Satan, the darkness that lies over the abyss, entered him.

(t. xxxii. 16.) Our Lord then said to Judas, That thou doest, do quickly, and the traitor this once obeyed his Master. For having received the sop, he started immediately on his work: He then having received the sop, went, immediately out. And indeed he did go out, not only from the house in which he was, but from Jesus altogether. It would seem that Satan, after he had entered into Judas, could not bear to be in the same place with Jesus: for there is no agreement between Jesus and Satan. Nor is it idle enquiring why after he had received the sop, it is not added, that he ate it. Why did not Judas cat the bread, after he received it? Perhaps because, as soon as he had received it, the devil, who had put it into his heart to betray Christ, fearful that the bread, if eaten, might drive out what he had put in, entered into him, so that he went out immediately, before he ate it. And it may be serviceable to remark, that as he who eateth our Lord's bread and drinketh His cup unworthily, eateth and drinketh to his own damnation; so the bread which Jesus gave him was eaten by the rest to their salvation, but by Judas to his damnation, inasmuch as after it the devil entered into him.

(t. xxxii. 16.) The time of night corresponded with the night which overspread the soul of Judas.

(Hom. lxxii. 2.) It follows: And it was night, to show the impetuosity of Judas, in persisting in spite of the unseasonableness of the hour.

"He then, having received the morsel of bread, went immediately out: and it was night." And he that went out was himself the night. "Therefore when" the night "was gone out, Jesus said, Now is the Son of man glorified." The day therefore uttered speech unto the day, that is, Christ did so to His faithful disciples, that they might hear and love Him as His followers; and the night showed knowledge unto the night, that is, Judas did so to the unbelieving Jews, that they might come as His persecutors, and make Him their prisoner.

In haste he hurries away in obedience to the will of Satan, and like one stung and goaded on to madness he rushes from the house. He sees nothing that can overcome his love of gain, and, marvellous though it is, we shall find him in no way benefited by the gift from Christ, of course because of his irrepressible inclination for getting money. For, completely overpowered by his passion, and possessed heart and soul by the father of all iniquity, the wretched man henceforward cannot even discern whither he is rushing on. So with his soul sunk in a night of its own, and darkened by a gloom-bringing swarm of unholy thoughts, he falls headlong into the abyss of Hades as into a trap; and, according to the saying in Proverbs, he flees away as a stag smitten to the liver with a dart, or like a dog into chains, and knoweth not that he runneth with peril of his life. And it seems to me that the inspired Evangelist did not without a purpose say that, having received the sop, he straightway went out. For Satan is terribly wont to urge on those whom he has once captured, and who have once for all fallen into his power, to straightway accomplish their evil works; and, throwing aside all delay, to compel them even against their will to carry out his pleasure. He fears, perhaps, with his usual bitterness of spirit and continual maliciousness, lest perchance in the interval of postponement some change of mind should overtake the man, inducing him to repent and to form a good resolution, and causing him to lay aside his pleasure in sin as a drunkard might leave off drunkenness; and so drag out of his net a victim whom he had deemed already caught in its toils. For this reason I suppose the offender harasses ever those who have fallen into his power, urging them to make great haste and speed in doing whatever is pleasing to him. For instance, he compels Judas, straightway after receiving the sop, as holding him now in his power, at once to proceed to that unholy deed; being very probably afraid as well of his repentance as of the effective power of Christ's gift, lest this, shining as a light in the heart of the man, should persuade him rather to make a deliberate choice of well-doing, or at any rate should give birth to the genuine honest temper of one who had been at length persuaded against his better feelings even to attempt the betrayal.

For that this is ever the wont of the demon in working against us we shall also see to be the case from what happened by way of type. The Jews were in subjection to Pharaoh while still in Egypt, and being by his orders sore vexed with laborious tasks in working with clay and making bricks, were allowed no time for the services they owed to God. For instance, Pharaoh says to the overseers of their tasks: Let the tasks of these men be made heavier, and let them not regard vain words; meaning by "vain words" their eagerness to escape to a state of freedom, their ardent passionate longing for this object, their lamentations over their slavery, and prayer for the greatest blessings. For he was not ignorant that in the leisure time which would be spent on these they would find great comfort. Passing then from the types to the perfect knowledge of the truer meanings, we shall find Satan ever hurrying onward to perform their wickedness those who have once fallen within his snares, and urging on those over whom he has already won a complete victory to be the ministers of such evil deeds as please him.

And leaving the sheepfold, [Judas] hurried to the beasts of prey, leaving behind the lambs.

(ii. Mor. 11) By the time of the day is signified the end of the action. Judas went out in the night to accomplish his perfidy, for which he was never to be pardoned.

"It was night when he went out." The Evangelist did not note without purpose that "it was night," but in order to teach us that not even the time hindered Judas, but even at night he was occupied with treachery.
It seems to me that Judas went out at the fifth hour of the evening, when Satan also entered into him. For at the fourth hour Satan attacked Judas, namely: when the woman mentioned by the Evangelist Matthew (Matt. 26:6–16) poured out the myrrh, and Judas went and made an agreement with the Jews concerning the betrayal. But at the fifth hour of the evening Satan entered into Judas, that is, he took possession of his heart. For it is one thing to strike someone with the hand from the outside, and another to plunge a sword into him and pierce his inward parts.
Judas "went out" from the Savior both physically and mentally. "It was night," perhaps also a mental night, that is, the darkness of avarice that had enveloped him.

When therefore he had received the morsel, he went out immediately, so that he might swiftly fulfill it. And the time was fitting for the deed; and it was night; Job twenty-four: "The eye of the adulterer watches for darkness"; and above, chapter three: "He who does evil hates the light."

Next (v 30), John shows that what was predicted came about. First, he mentions the action which was done; secondly, the time when it was done.

What was done was done quickly, because after receiving the morsel, he immediately went out. Note that, as Origen says, the Evangelist does not say that Judas ate the morsel, but that he received it. This can be understood in two ways. First, it could be that Judas was so troubled about obeying the Teacher that when he received the morsel, he did not eat it, but perhaps left it on the table and without delay went out to complete his betrayal. The reason for this could be that the devil did not allow Judas to eat the bread. For the devil, who had already entered into the heart of Judas, feared that if Judas ate the bread, the devil would have to leave, since he could not be in the same place as Jesus: "What accord has Christ with Belial?" (2 Cor 6:15); "You cannot drink the cup of the Lord and the cup of demons" (1 Cor 10:21).

Taken the other way, we could think that Judas ate the bread he received. Then the meaning is, after receiving the morsel, not only in his hand, but even eating it, he immediately went out. He thus made use of a good thing in a bad way. This is exactly what someone does who unworthily eats the bread of the Lord, or drinks from his chalice: he eats and drinks to his own damage and adds to his sin. So the bread Jesus gave to Judas became a source of harm: for after the bread entered into him so did Satan.

The time is described as one of darkness: and it was night. He mentions this for two reasons. First, to emphasize the malice of Judas. It had grown in his heart to such a degree that even the inconvenience of the hour did not cause him to wait till the morning: "The murderer rises in the dark...and in the night he is as a thief" (Job 24:14).

In the second place, he wants to show his state of mind. It was night, because the mind of Judas the traitor was dark, without divine light. "If any one walks in the day, he does not stumble, because he sees the light of this world. But if any one walks in the night, he stumbles, because the light is not in him" (11:9-10).