Appears 5 times in the Quran. (Root: علم)
  1. And thus We have made you a medium (just) nation that you may be the bearers of witness to the people and (that) the Messenger may be a bearer of witness to you; and We did not make that which you would have to be the qiblah but that We might distinguish him who follows the Messenger from him who turns back upon his heels, and this was surely hard except for those whom Allah has guided aright; and Allah was not going to make your faith to be fruitless; most surely Allah is Affectionate, Merciful to the people.

  2. They said: We desire that we should eat of it and that our hearts should be at rest, and that we may know that you have indeed spoken the truth to us and that we may be of the witnesses to it.

  3. Then We raised them up that We might know which of the two parties was best able to compute the time for which they remained.

  4. And he has no authority over them, but that We may distinguish him who believes in the hereafter from him who is in doubt concerning it; and your Lord is the Preserver of all things

  5. And most certainly We will try you until We have known those among you who exert themselves hard, and the patient, and made your case manifest.