SimchaMinute by Rabbi Avigdor Miller
[When his guests said to Avraham], "We wish to express our gratitude to you," he said, "No, thank the Master of this garden!"
They said, "Where is the master?"
And he said, "There!" He pointed upwards, and he explained to them and they all repeated after him the words, "We thank You our G-O-D, the Master of the world who created the fruit of the trees." That was a demonstration. Of what? A demonstration of the kindness of Hashem. — A Happy World (#371)