Siman 214

In every berakhah there must be the Name and Sovereignty and the Universe: "Blessed are You, Hashem our G-d, King of the universe," and any berakhah that does not contain the Name and Sovereignty is not a berakhah. And if one omitted the Name or Sovereignty, he must return and recite the berakhah again; and even if he only omitted the word "the universe" alone, he must return and recite the berakhah again, for "King" alone is not Sovereignty (Tosafot 40b, s.v. "Amar"), but if he omitted the word "our G-d," it implies that he does not need to return. And that which in berakhot that have an opening and a closing there is no "King of the universe" in the closing, is because since he mentioned it in the opening, he does not need to mention it in the closing, and when he says in the closing: "Blessed are You, Hashem," it refers back to the above (so it appears to me is the intent of the Tosafot ibid.).

And this is why in the blessing of the Patriarchs in the prayer there is no "King of the universe," for since we say "God of Abraham," it is like kingship, for Abraham our forefather crowned the Holy One, blessed be He, over the entire world. And similarly in the blessing of "Magen Avot," since we say: "The holy King like whom there is none" or "The holy God like whom there is none," it is like "King of the universe" (Tosafot ibid.). And similarly in "Elohai Neshamah" according to the one who holds that it is not adjacent to the blessing of "Asher Yatzar" and contains no kingship, for since he mentions in it that the Holy One, blessed be He, creates the souls and breathes them into bodies and afterwards takes them from them and afterwards returns them to them, you have no greater kingship than this (Beit Yosef). And a blessing adjacent to its fellow does not require "King of the universe," for behold, the opening of the first one applies to all of them.

And some say that that which the Sages, of blessed memory, said: "Any blessing that does not contain mention of Sovereignty is not a blessing," this refers to blessings over pleasures, blessings over mitzvot, and blessings of sight, which are an expression of thanks to the Holy One, blessed be He; in these it is appropriate to mention Him, may He be blessed, as "King of the universe." However, regarding prayer, the essence of which is the request for one's needs, except that beforehand one must arrange the praise of the Omnipresent—regarding this the Sages, of blessed memory, did not say so, and therefore there is no "King of the universe" in the prayer (Bach in the name of our teacher, Yaakov Pollack, and similarly the Beit Yosef wrote in the name of the Rokeach, see there). And the reason seems to me to be that regarding all the blessings we enumerated, every human species benefits from His creation, may He be blessed, and therefore it is necessary to mention "King of the universe." But in the prayer unique to us, where we say: "Our God and God of our fathers, etc.," how is "King of the universe" relevant? And in the blessing over mitzvot we say "King of the universe" because we say "Who has sanctified us with His mitzvot," meaning from all the nations, it is necessary to say "King of the universe," as is understood.

The Rambam wrote in chapter 11 of Berakhot, law 5: "One who performs a mitzvah and did not recite a blessing, if it is a mitzvah whose performance is still extant—he blesses after the performance. For example, if he wrapped himself in tzitzit or donned tefillin or sat in a sukkah and did not bless—he blesses afterward, for he is still performing the mitzvah. But if it is a matter where the mitzvah has passed—he does not bless, for example, if he slaughtered and did not bless or covered the blood and did not bless, etc." Thus far his words. And there are those who disagree with him, for even in such a case, if he did not bless, he blesses afterward, and only regarding a blessing over pleasure does he not bless afterward, but not regarding a blessing over the mitzvot; and we explained this in Yoreh Deah siman 19, see there.