In the days of Rabbi Tanchuma, a drought took hold of the land. With parched fields and dwindling supplies, the people looked toward the azure sky with desperation. If rain didn’t fall soon, they would all perish.

The people came before Rabbi Tanchuma and begged him, “Our teacher! Declare a communal fast so that we may fast and pray, and rain will fall!”

Rabbi Tanchuma declared a fast, but still, no rain came. He declared another fast, yet still, no rain fell. On the third occasion, he stood before the congregation and urged each person to fulfill acts of charity to the best of their ability so that they would be deserving of rain.1

One of the men who heard Rabbi Tanchuma’s teaching went home, gathered up whatever money he could find, and went to the marketplace.

There, he encountered his ex-wife.

She approached him and said, “May I merit a charitable act today, for since the day you divorced me, nothing good has ever happened to me.”

The man could see that she was in dire straits indeed—she lacked proper clothing and was in great distress. Filled with compassion, he gave her the bundle of money and went on his way.

While the couple was standing there, they were observed by a passing individual who thought the worst of them.

Suspecting that they were acting improperly, the man approached Rabbi Tanchuma and said, "Honored Rabbi, how can you sit here in the study hall while terrible sins are happening in our community!?

“What did you see?” Rabbi Tanchuma asked him.

“I saw so and so speaking with his ex-wife in the marketplace and he even handed her cash. I can only imagine why …”

Rabbi Tanchuma ordered that the man suspected of misconduct be brought before him.

When the confused fellow appeared, Rabbi Tanchuma said to him, “My son, don’t you know that the world is in distress? We are suffering, and even animals are in distress. Yet you are hanging out with your divorcee and even giving her money? Don’t you realize that this behavior is inappropriate?”

The man responded, “Didn’t you yourself teach us that the verse ‘Do not ignore your flesh’ means that one must be kind to his ex-wife? And didn’t you say that everyone should fulfill acts of charity? Inspired by your words, I took what I had and went to seek a mitzvah. I met my ex-wife and it was clear to me that there would be no better recipient of my charity than her!”

At that moment, Rabbi Tanchuma lifted his eyes to the heavens and said, “Master of the Universe! The nature of people is to be mean toward our ex-spouses, and this man has no obligation to feed his former wife. Yet he was kind to her. How much more are You obligated to care for us, descendants of Abraham, Isaac, and Jacob! We rely on You alone. Please! Give us the rain we need!”

And at that very hour, rain began to fall, drenching the parched fields, filling rivers and creeks, bringing life and sustenance back to the land and its people.

Source: Vayikra Rabbah Behar