Quran 102:5 from Surah At-Takaathur on Divine Marvels.
كـَلَّا لَوۡ تَعۡلَمُونَ عِلۡمَ ٱلۡيَقِينِ
English translation: Nay! If you know (with) a knowledge (of) certainty
Transliteration: kalla law ta'lamuna il'ma al-yaqini