The word(s) "sterner" appears 2 time(s) in 2 verse(s) in Quran in Muhammad Pickthal translation.

(1) (Pharaoh) said: Ye put faith in him before I give you leave. Lo! he is your chief who taught you magic. Now surely I shall cut off your hands and your feet alternately, and I shall crucify you on the trunks of palm trees, and ye shall know for certain which of us hath sterner and more lasting punishment.

(2) Thus do We reward him who is prodigal and believeth not the revelations of his Lord; and verily the doom of the Hereafter will be sterner and more lasting.