“When Jesus understood it, he said unto them, Why trouble ye the woman? for she hath wrought a good work upon me.”
Matthew 26:10 — Greek Interlinear
Church Fathers on Matthew 26:10
Having set before us the counsels of the chief of the Jews concerning the death of Christ, the Evangelist would proceed to follow out their execution, and to relate the bargain of Judas with the Jews to deliver Him up, but be first shews the cause of this betrayal. He was grieved that the ointment which the woman poured upon Christ’s head had not been sold that he might have carried off something out of the price it brought, and to make up this loss he was willing to betray…
Not that he was a leper yet, but having been so, and having been healed by the Saviour, be retained the appellation to shew forth the power of Him who healed him.
'Alabaster' is a kind of marble, white but marked with veins of different colours, which was in use for vessels to hold ointment, because it was said to preserve it from corruption.