What is the meaning of "Happy is the man who listens to me?" The Holy One, Blessed be He, said: "Happy is the man whose hearing is devoted to me."
The theology of Deuteronomy is hard to swallow. It is the classic if-then formula: if we obey God's commandments, then God will reward us. This is stated explicitly in Ki Tavo, where the midrash jumps off in Deuteronomy 28:1: "Now, if you obey the Lord your God, to observe faithfully all His commandments which I enjoin upon you this day, the Lord your God will set you high above all the nations of the earth." The historical-critical reader sees in this a retroactive assignation of guilt by those who witnessed the destruction of the First Temple: if only we had obeyed, the Temple would not have been destroyed, and we would not have been shamed before the nations. But the reader seeking spiritual nourishment from the Torah text has to face the fact that, historical explanations aside, bad things happen to good people—including ones who do obey God's mitzvot.
But what if "obeying" or "listening to" is not literal—what if we take it, instead, to be about the way we incline our hearts and ears as we walk through life? Our emotional states are about what takes place "inside" ourselves no matter the conditions and happenings of our physical lives "outside." We can't control what happens to us, but we can control our attitude. To that extent, we do have control over our happiness. We can walk through life with our hearing attuned to the negative or we can devote our hearing to things that are godly. I recall a rabbi once noticing that our ears are always open—unlike our mouths or hands—and so it is up to us in our inner lives to decide how to listen. We might not all be happy all of the time, and we certainly do not all get what we deserve, no matter what the classic Deuteronomic theology has to say. But, we can attune ourselves to hearing God's goodness in the world, and strive to listen with devotion for what can bring us joy.