John Calvin Commentary John 12:3

"Mary therefore took a pound of ointment of pure nard, very precious, and anointed the feet of Jesus, and wiped his feet with her hair: and the house was filled with the odor of the ointment." — John 12:3 (ASV)

And the house was filled with the odor of the ointment. It was not a simple liquid extracted from spikenard, but a compound of many fragrant substances; and therefore it is no wonder that the whole house was filled with the odor.