What is the meaning of "Asafta"?
Radak: This is like "Asfu Nagham" (Yo'el 4:15 - they gathered their radiance and ceased to shine), "Asaf Elokim Es Cherpasi" (Bereishis 30:23).
What is the grammatical form of "me'Charon"?
Radak: It is Makor (like an infinitive), with a Nun added at the end, like me'Charos. It is unlike "Shuv me'Charon Apecha" (Shemos 32:12); that is a noun Samuch to Apecha. If it were a noun here, it would say Shavta me'Charon Apecha. Rather, Hashivosa is Po'el Yotzei; the object is Apecha. It is as if it says, You turned back Your anger, so it will not flare.
Are "Evrah" and "Af" the same?
Malbim: No. Charon Af is on the sinner. Evrah is when anger at the sinner breaches the border, to be angry also at people who did not sin. Therefore, the punishment of Yisrael is attributed to Charon Af, for they sinned. The punishment of the land is attributed to Evrah, for the land did not sin.
Why does he mention that Hashem's anger ceased?
Malbim: Since there is no more anger, now should be fulfilled the Nevu'os of the permanent salvation. Therefore, I request...