Shemot Rabbah, a collection of Midrashic interpretations on the Book of Exodus, offers a fascinating insight into this very question, focusing on Moses after the splitting of the Red Sea. It all starts with the verse, "Then Moses sang…" (Exodus 15:1). But what prompted this song?

The Midrash, specifically Shemot Rabbah 23, draws a beautiful connection to the Song of Songs 4:11, "Your lips drip nectar, my bride." It suggests that Moses, in his moment of praise, was actually atoning for a past transgression. He was using the very instrument of his sin – his speech – to laud God.

Imagine this: Moses essentially tells God, "Master of the universe, I praise You with the very thing I used to sin against You." It’s a powerful image, isn’t it?

Rabbi Levi bar Ḥiya illustrates this with a compelling parable. A province rebels against a king, and the king’s duke doubts the king’s ability to quell the rebellion. The king, without a word, secretly conquers the province. The duke, realizing his mistake, presents the king with a crown, explaining that it’s an apology for his lack of faith. He’s saying, "I doubted you, and now I honor you because of my doubt."

So, how did Moses specifically sin? The Midrash points to the word az (אז), which means "then" or "since." Moses had previously said, "Since [me’az – מאז, a form of az] I came to Pharaoh to speak in Your name, he has harmed this people, and You did not rescue Your people" (Exodus 5:23). In essence, Moses questioned God's actions. Now, after the miraculous crossing of the Red Sea, he begins his song with az, turning his former doubt into a declaration of praise: "Then Moses sang…"

The Midrash emphasizes a profound principle: the righteous can atone with the very thing they used to sin. "Come and see the path of the righteous, with that with which they sin and they atone," the text urges. It's a transformative idea.

But where does this concept originate? The Midrash claims it is from God Himself, "as with that that He strikes, He heals." The proof text? Jeremiah 30:17: "For I will restore health to you, and I will heal you of your wounds." The Midrash even interprets "of your wounds" as "with your wounds," meaning God uses the very source of our pain to bring about healing.

Think about the story of Mara. The Israelites are thirsty, but the water is bitter. God shows Moses a tree, and when Moses casts it into the water, the water becomes sweet (Exodus 15:25). What kind of tree was it? The Rabbis differ – Rabbi Natan says it was oleander, Rabbi Yehoshua says it was a willow, Rabbi Eliezer HaModa’i says it was an olive tree. But the key point is that it was a bitter tree that sweetened the bitter water.

Just as the bitter tree healed the bitter waters, Moses used the word az, the word with which he had complained, to sing praises to God. He transformed his doubt into affirmation, his complaint into a song.

What about us? Can we learn to transform our mistakes into opportunities for growth and praise? Can we use the very things that cause us pain to bring healing to ourselves and others? Perhaps the story of Moses and the waters of Mara can inspire us to find the sweetness even in the most bitter of circumstances.