As we will see in Mitzvah #433, there is an obligation for us to try to get closer to God through prayer. To help us fulfill this, our Sages established a prayer to be recited thrice-daily, corresponding to the prayers of our Forefathers. This prayer is called the Amidah (because it is recited standing); the weekday version is also called Shemoneh Esrei, the Eighteen Benedictions (although a nineteenth has since been added). Once a week for nineteen weeks, we will review the contents of the 19 blessings of “Shemoneh Esrei.”
The focus of the third blessing is God’s holiness. We know that the Torah is holy, Israel is holy and God is holy, but what exactly is “holiness?” Kadosh, translated as “holy,” more specifically means that something is special and set apart from the herd. This specialness approaches uniqueness but God, Who is One of a kind, is the Most Holy and the source of all holiness.
The blessing addresses God, saying that “Your holy ones will praise You every day, forever.” On one level, this refers to God’s ministering angels, who praise Him constantly (as we will discuss further in a moment). On another level, it refers to the Jews, a nation apart, who praise God daily through prayers such as this.
During the public repetition of the Shemoneh Esrei, this bracha is where the interactive Kedusha is recited. In this prayer, we emulate the manner in which the Heavenly beings praise God. For example, this is why we stand with our feet together, since angels are described as having a single “straight leg” (Ezekiel 1:7). We recite verses praising God’s attributes of holiness, particularly as sung by the angels: “Holy, holy, holy…” is from Isaiah 6:3, “Blessed is the honor…” is from Ezekiel 3:12 and “God will reign forever…” is from Psalms 146:10. (That last one is from King David, not from the angels, which it why that phrase is prefaced with, “And in the words of your holy ones it is written…”)
During the Ten Days of Repentance from Rosh Hashana through Yom Kippur, the closing of this blessing, normally “ha(k)Eil haKadosh” (“the holy God”) is replaced by “haMelech haKadosh” (“the holy King”). This reflects the time’s enhanced attribute of justice (as opposed to that of mercy, which has more sway the rest of the year).