Berakhot 46B

ויש מהן שחותם בהן ב״ברוך״ ואין פותח ב״ברוך״. ו״הטוב והמטיב״ פותח ב״ברוך״ ואין חותם ב״ברוך״. מכלל דברכה בפני עצמה היא.

and there are among these blessings that one who recites it concludes reciting it with: Blessed, but does not begin reciting it with: Blessed. The blessing: Who is good and does good, one who recites it begins to recite it with: Blessed, but does not conclude reciting it with: Blessed. This proves by inference that it is an independent blessing.

ואמר רב נחמן בר יצחק: תדע ד״הטוב והמטיב״ לאו דאורייתא ⁠— שהרי עוקרין אותה בבית האבל. כדתניא: מה הם אומרים בבית האבל? ״ברוך הטוב והמטיב״. רבי עקיבא אומר: ״ברוך דיין האמת״.

And Rav Naḥman bar Yitzḥak said: Know that the blessing: Who is good and does good, is not required by Torah law, as it is eliminated in the house of the mourner, as it was taught in a baraita according to the opinion of R' Akiva: What do they say in the house of the mourner? Blessed…Who is good and does good. R' Akiva says: Blessed…the true Judge.

״הטוב והמטיב״⁠ — אין, ״דיין אמת״⁠ — לא?! אלא אימא אף ״הטוב והמטיב״.

The first opinion in the baraita is challenged: Who is good and does good, yes, it is recited in the house of the mourner, the true Judge, no, it is not recited? Rather, say: Who is good and does good, is recited as well.

מר זוטרא איקלע לבי רב אשי, איתרע ביה מלתא, פתח ובריך: ״הטוב והמטיב, אל אמת, דיין אמת, שופט בצדק, לוקח במשפט, ושליט בעולמו לעשות בו כרצונו, כי כל דרכיו משפט, שהכל שלו ואנחנו עמו ועבדיו, ובכל אנחנו חייבים להודות לו ולברכו, גודר פרצות בישראל הוא יגדור את הפרצה הזאת בישראל לחיים״.

The Talmud recounts: Mar Zutra happened to come to Rav Ashi’s home when an incident of mourning befell Rav Ashi. Mar Zutra began a combined blessing and recited: Who is good and does good, God of truth, the true Judge, Who judges with righteousness, takes away with justice, and is the ruler of His world to do in it as He wills, as all His ways are just, that all is His and we are His people and His servants, and in everything we are obligated to thank Him and bless Him, Who repairs the breaches in Israel, He will repair this breach in Israel for life. Mar Zutra included both: Who is good and does good, as well as mourning and acceptance of divine justice.