The word(s) "weakness" appears 7 time(s) in 4 verse(s) in Quran in Muhammad Pickthal translation.

(1) Now hath Allah lightened your burden, for He knoweth that there is weakness in you. So if there be of you a steadfast hundred they shall overcome two hundred, and if there be of you a thousand (steadfast) they shall overcome two thousand by permission of Allah. Allah is with the steadfast.

(سورة الأنفال, Al-Anfaal, Chapter #8, Verse #66)
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(2) Allah is He Who shaped you out of weakness, then appointed after weakness strength, then, after strength, appointed weakness and grey hair. He createth what He will. He is the Knower, the Mighty.

(سورة الروم, Ar-Room, Chapter #30, Verse #54)
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(3) And We have enjoined upon man concerning his partners - His mother beareth him in weakness upon weakness, and his weaning is in two years - Give thanks unto Me and unto thy parents. Unto Me is the journeying.

(سورة لقمان, Luqman, Chapter #31, Verse #14)
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(4) He whom we bring unto old age, We reverse him in creation (making him go back to weakness after strength). Have ye then no sense?

(سورة يس, Yaseen, Chapter #36, Verse #68)
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