HaGaon HaTzadik MiPapa, R’ Yosef Greenvald, in his sefer Vayechi Yosef (pg. 38) explains that since the frogs were moiser nefesh [gave up their lives] to enter into ovens – they wanted to stay there, out of love for the mitzvah of dying al pi kiddush Hashem, a regular tefillah wouldn’t help override the tefillah of the frogs, therefore, Moshe needed to scream and daven a special tefillah.
Here is what the Vayechi Yosef writes:
The Gemara in Pesachim (53b) asks: What did Chananyah, Mishoel and Azariyah see to make them give up their lives by jumping into a fire? The Gemara answers: They made a kal v’chomer from the frogs, if frogs which have no mitzvah of kiddush Hashem jumped into the ovens, then us, who are commanded in the mitzvah of kiddush Hashem must certainly be prepared to go into ovens and be prepared to die.
Tosfos asks: Why did Chananyah, Mishoel and Azariyah need to make a kal v’chomer, they were being forced to serve avodah zorah in public and one must be prepared to give up his life to avoid transgressing even a light aveirah in public, and certainly a severe aveirah like avodah zorah? Tosfos answers, that it wasn’t real avodah zorah.
However, if Tosfos is correct, then we can ask on the kal v’chomer: The frogs were directly commanded to enter into the ovens, however, Chananyah, Mishoel and Azariyah weren’t as it wasn’t real avodah zorah, if so, what is the kal v’chomer?
We can answer: All it says in the Torah is that the frogs should go into “the ovens and into the utensils used for putting things into the oven”, and this can be interpreted as meaning that the frogs should go into the ovens when they were cold, however, out of love for the mitzvah they went above and beyond and entered into the ovens whilst they were hot. From here Chananyah, Mishoel and Azariyah derived that if the frogs were moiser nefesh when they weren’t commanded, then how much more so must we be prepared to be moiser nefesh.
According to this we can answer: Since the frogs were moiser nefesh to enter the burning ovens out of love for fulfilling the word of Hashem, they didn’t want to leave, as the mitzvah was very beloved to them, therefore, it wasn’t enough for Moshe to simply daven a regular tefillah that they should leave, as they were refusing to leave. Consequently, it says “Moshe screamed out to Hashem”, as he had to daven with greater strength and greater power, like we find that a loud voice arouses kavonah, in order to remove the frogs.”
