The word(s) "stern" appears 6 time(s) in 5 verse(s) in Quran in Mohsin Khan translation.

(1) O you who believe! Whoever from among you turns back from his religion (Islam), Allah will bring a people whom He will love and they will love Him; humble towards the believers, stern towards the disbelievers, fighting in the Way of Allah, and never fear of the blame of the blamers. That is the Grace of Allah which He bestows on whom He wills. And Allah is All-Sufficient for His creatures' needs, All-Knower.

(2) And We made the people who were considered weak to inherit the eastern parts of the land and the western parts thereof which We have blessed. And the fair Word of your Lord was fulfilled for the Children of Israel, because of their endurance. And We destroyed completely all the great works and buildings which Fir'aun (Pharaoh) and his people erected.

(3) And you (O Muhammad صلى الله عليه وسلم) were not on the western side (of the Mount), when We made clear to Musa (Moses) the commandment, and you were not among the witnesses.

(4) O you who believe! Ward off yourselves and your families against a Fire (Hell) whose fuel is men and stones, over which are (appointed) angels stern (and) severe, who disobey not, (from executing) the Commands they receive from Allah, but do that which they are commanded.

(5) 'And we have sought to reach the heaven; but found it filled with stern guards and flaming fires.