Which preposition to use with amalek

from Occurrences 9%

Moses then edified an altar unto our Lord, and called there on the name of our Lord, saying: The Lord is mine exaltation, for this is the hand only of God, and the battle and God shall be against Amalek from generation to generation.

under Occurrences 1%

Our Lord said to Moses: Write this for a remembrance in a book and deliver it to the ears of Joshua; I shall destroy and put away the memory of Amalek under heaven.

Which preposition to use with  amalek