Appears 3 times in the Quran. (Root: توب)
  1. And repentance is not for those who go on doing evil deeds, until when death comes to one of them, he says: Surely now I repent; nor (for) those who die while they are unbelievers. These are they for whom We have prepared a painful chastisement.

  2. And when Musa came at Our appointed time and his Lord spoke to him, he said: My Lord! show me (Thyself), so that I may look upon Thee. He said: You cannot (bear to) see Me but look at the mountain, if it remains firm in its place, then will you see Me; but when his Lord manifested His glory to the mountain He made it crumble and Musa fell down in a swoon; then when he recovered, he said: Glory be to Thee, I turn to Thee, and I am the first of the believers.

  3. And We have enjoined on man doing of good to his parents; with trouble did his mother bear him and with trouble did she bring him forth; and the bearing of him and the weaning of him was thirty months; until when he attains his maturity and reaches forty years, he says: My Lord! grant me that I may give thanks for Thy favor which Thou hast bestowed on me and on my parents, and that I may do good which pleases Thee and do good to me in respect of my offspring; surely I turn to Thee, and surely I am of those who submit.