Translator's note: In this discourse, Mara and the Buddha are speaking different languages. By "acquisitions" Mara means one's family and physical possessions. The Buddha uses the same word to mean a sense of possession for anything — physical or mental — at all.
I have heard that on one occasion the Blessed One was staying near Savatthi in Jeta's Grove, Anathapindika's monastery. Then Mara the Evil One went to the Blessed One and recited this verse in his presence:
[The Buddha:]Those with children grieve because of their children. Those with cattle grieve because of their cows. A person's grief comes from acquisitions, since a person with no acquisitions doesn't grieve.
Then Mara the Evil One — sad & dejected at realizing, "The Blessed One knows me; the One Well-Gone knows me" — vanished right there.