The word(s) "strengthen" appears 8 time(s) in 8 verse(s) in Quran in Saheeh International translation.

(1) [Remember] when your Lord inspired to the angels, "I am with you, so strengthen those who have believed. I will cast terror into the hearts of those who disbelieved, so strike [them] upon the necks and strike from them every fingertip."

(2) And if We had not strengthened you, you would have almost inclined to them a little.

(3) And those who disbelieve say, "Why was the Qur'an not revealed to him all at once?" Thus [it is] that We may strengthen thereby your heart. And We have spaced it distinctly.

(4) [Allah] said, "We will strengthen your arm through your brother and grant you both supremacy so they will not reach you. [It will be] through Our signs; you and those who follow you will be the predominant."

(5) When We sent to them two but they denied them, so We strengthened them with a third, and they said, "Indeed, we are messengers to you."

(6) And We strengthened his kingdom and gave him wisdom and discernment in speech.

(7) Muhammad is the Messenger of Allah; and those with him are forceful against the disbelievers, merciful among themselves. You see them bowing and prostrating [in prayer], seeking bounty from Allah and [His] pleasure. Their mark is on their faces from the trace of prostration. That is their description in the Torah. And their description in the Gospel is as a plant which produces its offshoots and strengthens them so they grow firm and stand upon their stalks, delighting the sowers - so that Allah may enrage by them the disbelievers. Allah has promised those who believe and do righteous deeds among them forgiveness and a great reward.

(8) We have created them and strengthened their forms, and when We will, We can change their likenesses with [complete] alteration.