The most important duty of children toward their parents is Hakarat Hatov — recognizing the good. For ultimately we are here thanks to our parents: they are the ones who brought us into the world.

In our Parasha the Ten Plagues begin. Something striking appears in the first three: Blood (דָּם) strikes the Nile, Frogs (צְפַרְדֵּעַ) rise from the Nile, Lice (כִּנִּים) come from the earth — and each time Hashem tells Moshe: "Tell Aharon..."

Moshe and Aharon stand together before Pharaoh, but it is Aharon who raises the staff and strikes, not Moshe. Why?

Our Sages answer: because of Hakarat Hatov. The Nile had protected the infant Moshe — when his mother could no longer hide him she set him in a basket on the river, and the water did not drown him. The earth, too, had "helped" Moshe at age twenty: after he struck the Egyptian who was beating a Hebrew, the sand opened to conceal the body.

One might object: the Nile and the earth are Domem, inanimate! What do they feel? Nothing. Creation unfolds in four degrees:

Return to the beginning. Moshe and Aharon come before Pharaoh with Hashem's message.

"Thus says Hashem, G-d of Israel: Let My people go!" Pharaoh's answer is a challenge:

"Who is Hashem that I should heed His voice? I do not know Hashem!" He searches his "Google" and finds nothing. The Ten Plagues then come to make the introductions: "You want to know who Hashem is? Here."

Picture all of reality as a graph rising step by step. The plagues climb the ladder of the world: Blood beneath the Nile's surface; the amphibious Frogs between water and land; Lice from the dust; Wild Beasts walking upon the ground; Pestilence in the air we breathe; Boils from soot cast skyward; Hail, fire and ice between earth and sky; Locusts that hide the sun; Darkness that veils the heavenly lights.

The tenth plague, the death of the Firstborn, reaches the summit: in Egypt the Bechorot were like the priests of the cult — the level they held to be "divine."

Pharaoh took himself for a god. He did not say "I made the Nile" — for then he'd be asked "who made you?" — but rather:

"The Nile is mine, and I made myself." He would even relieve himself secretly in the Nile, so none would know he had human needs.

"Ten Plagues" at once recalls the Ten Utterances by which the world was created (עֲשָׂרָה מַאֲמָרוֹת) and the Ten Commandments (עֲשֶׂרֶת הַדִּבְּרוֹת). A correspondence binds these three "tens," leading to the Ten Sefirot through which Hashem directs the world: Keter, Chochma, Bina, Chesed, Gevura, Tiferet, Netzach, Hod, Yesod, Malchut.

From Hakarat Hatov flows an even greater principle: gratuitous love. If we owe gratitude even to the Domem, and honor to our parents, then we must also learn to love our fellow — even without apparent reason.