Tafsir of Ad-Dukhan 44:31

And indeed We saved the Children of Israel from the humiliating torment from Fir`awn; verily, he was arrogant and was of the excessive. Here Allah reminds them of how He saved them from their humiliation and subjugation at the hands of Fir`awn, when they were forced to do menial tasks

إنه كان عاليا من المسرفين

(verily, he was arrogant), means, he was proud and stubborn. This is like the Ayah:

إن فرعون عﻼ فى اﻻرض

Verily, Fir`awn exalted himself in the land, (28:4)

فاستكبروا وكانوا قوما علين

but they behaved insolently and they were people self-exalting, (23:46) He was one of the excessive and held a foolish opinion of himself

ولقد اخترناهم على علم على العالمين