And from that time he sought opportunity to betray him.

People's New Testament

26:16 From that time. The time of the bargain with the priests. No one can tell certainly what day the bargain was completed.

Matthew Henry's Concise Commentary

26:14-16 There were but twelve called apostles, and one of them was like a devil; surely we must never expect any society to be quite pure on this side heaven. The greater profession men make of religion, the greater opportunity they have of doing mischief, if their hearts be not right with God. Observe, that Christ's own disciple, who knew so well his doctrine and manner of his life, and was false to him, could not charge him with any thing criminal, though it would have served to justify his treachery. What did Judas want? Was not he welcome wherever his Master was? Did he not fare as Christ fared? It is not the lack, but the love of money, that is the root of all evil. After he had made that wicked bargain, Judas had time to repent, and to revoke it; but when lesser acts of dishonesty have hardened the conscience men do without hesitation that which is more shameful.