"When the Lord enlarges your territory, as He has promised you." [Deut. 12:20]
The promise of a large territory comes in the context of the various gifts and tithes the Torah requires the Israelites to give to the poor. Because of this conjunction, a midrash relates this verse to a verse in Proverbs (18:16) that uses the same verb: "A man’s gift enlarges him." A person’s generosity affects not only the recipient, but also the person giving.
The midrash tells the story of a man named Avun, whom they gave the nickname "the deceitful." But the nickname was actually a form of praise. Whenever an appeal for charitable funds was made in his community, Avun would keep quiet, as if he did not intend to pledge. Actually, he was only waiting to hear what others promised; he then gave as much money as all the other donors combined. When they realized the purpose of Avun’s "deception," the Sages gave him a place of honor. In that way, Avun demonstrated the truth of the verse, "A man’s gift enlarges him."
Giving not only helps the people who receive our generosity, it also improves us. We become "bigger" people, people who better appreciate needs beyond our personal ones At this time of year, when we receive many requests for tzedakah, we should bear this truth in mind as we make our decisions.