Ulum al Qur'an
The Qur'an on Naskh
The principle of naskh (abrogation) is referred to in the Qur'an itself and is not a later historical development:
'None of Our revelations do We abrogate or cause it to be forgotten, but We substitute something better or similar: knowest thou that God has power over all things?' (2: 106). [Some however say that this refers to the revelations before the Qur’an, which have now been substituted by the Qur’an itself. See Mawdudi. The Meaning of the Qur’an, Lahore, 1967, Vol. I, p.102. note 109.]