وَإِن And if wa-in you are kuntum in fī doubt raybin about what mimmā We have revealed nazzalnā to ʿalā Our slave ʿabdinā then produce fatū a chapter bisūratin [of] min like it mith'lihi and call wa-id'ʿū your witnesses shuhadāakum from min other than dūni Allah l-lahi if in you are kuntum truthful ṣādiqīna
And if you are in doubt about what We have sent down [i.e., the Qur’ān] upon Our Servant [i.e., Prophet Muḥammad (ﷺ)], then produce a sūrah the like thereof and call upon your witnesses [i.e., supporters] other than Allāh, if you should be truthful.
فَإِن But if fa-in not lam you do tafʿalū and never walan will you do tafʿalū then fear fa-ittaqū the Fire l-nāra whose allatī [its] fuel waqūduhā (is) [the] men l-nāsu and [the] stones wal-ḥijāratu prepared uʿiddat for the disbelievers lil'kāfirīna
But if you do not - and you will never be able to - then fear the Fire, whose fuel is people and stones, prepared for the disbelievers.