Passing Phrase - www.learnhebrew.org.il
Literally: At a time of boiling
Idiomatically: In the heat of the moment, in a moment of anger
This phrase is comprised of two words in Aramaic: "Idna" which in Hebrew would be "idan" (עידן), meaning time (Daniel 6:12), and "ritcha" from the Hebrew "roteach" (רותח) meaning to boil (Jerusalem Talmud Shabbat 4:2). The phrase itself can also be found in the Talmud (Baba Kama 60b). There is a wonderful Talmudic sentence (Ketuvot 106a), which in Hebrew would read
בשעת הכעס (בעידן רתחא) לא התפלל וביקש רחמים - אני אבקש רחמים.
In a moment of anger (he) did not pray and ask for mercy. I will ask for mercy.
In modern usage you would say
אין לדון אדם בעידנא דריתחא.
"Ain ladun adam be'idna deritcha."
Do not judge a person in his moment of anger.