Thank you for the interpretative question on, “What is the point of Matthew 26:6–13?”
As I read the text, there are three viewpoints on the woman’s action.
A. The woman wanted to show the depth of her love for Jesus.
B. The disciples wanted to rebuke the woman for the wasted resource on him instead of for the poor people.
C. Jesus wanted to share the purpose of God was to prepare him for his burial.
The key phrase by Jesus is that she has done a beautiful thing to me. The anointing of Jesus was expression of her love to Jesus even as she didn’t realize that it was in preparation for his burial. There are at times a greater purpose by God than our own actions.
Thus for me the point of the passage is this: One’s expression of love for Jesus will be honored by God. Nothing is wasted for God.
For more perspectives: