"May His Great Name be Exalted and Sanctified"
Ezekiel 38:23 reads, “I (God) will be exalted and I will be sanctified. I will make Myself known in the eyes of many nations so that they will know that I am God.” The words “I will be exalted and I will be sanctified” in Hebrew are “v’hisgadilti v’hiskadishti” (roots: GDL, large, and KDSh, holy). This expression is paraphrased by the opening words of Kaddish, “Yisgadal v’yiskadash shmei rabbah” – “May Your great Name be exalted and may it be sanctified…”
We see that the phraseology is Biblical in origin, but that’s only the tip of the iceberg. This choice of words also contains deeper significance. What are the ramifications of God being exalted and sanctified? To answer that, let us flip back two chapters, to Ezekiel 36:23-24:
“I will sanctify My great Name, which is desecrated among the nations, for you have desecrated it among them. Then, these nations will know that I am God,” says Hashem the Lord, “when I am sanctified through you in their sight. I will take you from among the nations and gather you from all the territories and I will return you to your own land.”
Aside from the juxtaposition of sanctification to God’s “great Name” (“shmei rabbah” in Kaddish), these two verses explain how God becomes sanctified. Rashi on verse 23 spells it out. He asks, “What is this sanctification?” and he responds with the next verse, “I will take you from among the nations…” In other words, God is sanctified when He redeems Israel. Our prayer that God be exalted and sanctified is simultaneously a prayer for redemption, as the two things are one and the same!
"Accept the Prayer and the Supplication"
The Kaddish Shaleim (“Whole Kaddish”) is recited after the conclusion of the major section of a prayer service. It includes a phrase that is not present in any other form of Kaddish: “tiskabeil tzlos’hon u’va’us’hon d’chol beis Yisrael” – “accept the prayer and the supplication of the entire Jewish people…” Not only is this a request that God find favor with the prayers just recited, it is another reference to very specific Bible sources.
The first is more famous, if less obvious. On his deathbed, the patriarch Jacob gave his son Joseph the city of Shechem telling his son that he acquired it “with my sword and my bow” (Genesis 48:22). Onkelos, the preeminent Bible translator, who typically explains metaphors, renders this in Aramaic, “bitzlosi uv’va’usi” – “with my prayer and my supplication” – the same words later chosen for use in Kaddish.
Less familiar is I Kings 8:45, describing the dedication of the Temple by King Solomon. Speaking of the non-Jews, who were also welcome to pray and to offer sacrifices to God at the Temple, he said, “May You in Heaven hear their prayer and their supplication in order to fulfill their desires.” The Targums again render prayer and supplication as tzlos’hon and va’us’hon. (Despite the metaphor, the verse in Genesis is generally accepted as the source of the phraseology. This may be because the referent in Kings is the prayer of non-Jews, while the referent in Kaddish is the prayer of Jews.)
"May the One Who Makes Peace Above Make Peace upon Us"
Finally, the closing phrase of every Kaddish except for the Chatzi Kaddish (“Half Kaddish”) is also Biblical in origin. Job 25:2 says that authority and dread are under the control of “the One Who makes peace in His lofty realms” (“Oseh shalom bimromav”). One explanation of God making peace in the Heavens is cited by Rashi there, as well as on Genesis 1:8. In Hebrew, Heaven is called Shamayim, a contraction of the words aish (fire) and mayim (water). God makes peace between these two forces of nature, which cannot peacefully coexist under normal circumstances, and from the result He has built the Heavens. If God can do this (and He can), He is certainly capable of making peace among us, His children who dwell below. We only pray that He do so soon!
So important is this prayer for peace from above that it is used of the closing sentiment of Kaddish, as well as at the end of the personal meditations found at the conclusion Shemoneh Esrei. (Different requests for peace conclude other prayers, from bentching to Birkas Kohanim.)
In conclusion, it is apparent that the words of Kaddish were carefully selected to convey deep messages far beyond the surface meaning of the words. The profound nature of this prayer befits its importance and prominence in our service of God.