Even the king began to shudder bodily: King Philopator also trembled in fear.

And he forgot his sullen insolence does not mean that he failed to remember his arrogance, only that his proud attitude was completely changed. His arrogance was completely gone.

A possible model for this verse is:

• Even the king began to tremble, and all his arrogance was gone [or, he was no longer filled with pride].

Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on 3-4 Maccabees. (UBS Helps for Translators). Miami: UBS, 2018. For this and other handbooks for translators see here.