Matthew 26:8 Meaning

6Now when Jesus was in Bethany, in the house of Simon the leper,

7There came unto him a woman having an alabaster box of very precious ointment, and poured it on his head, as he sat at meat.

8But when his disciples saw it, they had indignation, saying, To what purpose is this waste?

9For this ointment might have been sold for much, and given to the poor.

10When Jesus understood it, he said unto them, Why trouble ye the woman? for she hath wrought a good work upon me.