Why does the Torah not tell us the original name of Peni'el, like it did for Beis El (28:19)?
Oznayim la'Torah: The Torah already said that it was 'Ma'avar Yabok.' 1
Why was Yaakov enthused that he survived seeing an angel, "Panim El Panim"? Hashem had spoken with him!
Ohr ha'Chayim, Oznayim la'Torah: "Ra'isi... Panim El Panim" implies war, as in Melachim II 14:8.
Alshich: It was just the two of us. There were no other angels there to save me.
Malbim: Had Yaakov known Hashem only through investigation, he would not have been saved. Only because he had seen Hashem Panim El Panim (through prophecy), I was saved from the enticement of the Satan. 1
Malbim: This is like we say, that had Hashem not spoken to Yisrael Panim El Panim at Matan Torah, they would not have been able to stand up [to the pressure to abandon Torah] at the time of Shemad (decrees against Torah).
Why does it say here Peni'el, and in the next verse Penu'el (32:32)?
Radak: There is no difference. The letters [Aleph, Hei,] Vav and Yud are interchangeable. 1
R. Chaim Paltiel (to 32:32): Initially he called it Peni'el, based on "Panim." Later, it is called Penu'el - people should turn (Penu) to that place.
Alshich: Yaakov thought that he was saved due to the place (he saw camps of angels there; or Hashem made my face like Kel (the Midah of Chesed), so that Za'am - the power of fury of Esav's Sar - will have no effect ("v'Kel Zo'em b'Chol Yom" - Tehilim 7:12)). The Torah calls it Penu'el, to teach that Yaakov merited this himself; it was not due to the place.
Ohr ha'Chayim: The Torah itself (also the Navi in Shoftim 8) calls it Penu'el. Only Yaakov called it Peni'el.
Ha'amek Davar (to 32:31,32): Peni'el hints that my face (Panai) overcame the angel with Divine power. He thought that the angel did not overcome him at all, and he limped only due to the pain. The pain ended and he still limped; he understood that also the angel overcame him somewhat, so he called it Penu'el (plural).
We cannot attribute the change to the Ta'amei ha'Mikra. In both verses, the Ta'am is Esnachta!
