Jamieson, Fausset & Brown

said Jesus, Let her alone, against the day of my burying hath she done this--not that she thought of His burial, much less reserved any of her nard to anoint her dead Lord. But as the time was so near at hand when that office would have to be performed, and she was not to have that privilege even alter the spices were brought for the purpose (Mar 16:1), He lovingly regards it as done now.