5th Ayah from Surah At Takathur
No! If you only knew with knowledge of certainty...
No indeed! If only you knew for certain.
Nay! If you knew with a sure knowledge (the end result of piling up, you would not have occupied yourselves in worldly things)
No! Only if you knew (it) with a sure knowledge!
Nay, would that ye knew (now) with a sure knowledge!
Nay, were ye to know with certainty of mind, (ye would beware!)