Does the repentance of one who committed disbelief, trampled upon the Qur'an, and went to a sorcerer, knowing full well [the gravity of his actions], get accepted, bearing in mind that Allah does not forgive that partners be associated with Him, but He forgives whom He wills short of that, and He forgives those who do evil out of ignorance?

Trampling on the Mus'haf (Quran) or throwing it into filth constitutes apostasy from the religion. Going to a sorcerer is a sin. If someone commits any of these acts and then repents with sincere repentance, their repentance is accepted, based on the Almighty's saying: "Say, 'O My servants who have transgressed against themselves [by sinning], do not despair of the mercy of Allah. Indeed, Allah forgives all sins.'" (Quran 39:53), and the Prophet's (PBUH) saying: "Indeed, Allah Almighty accepts the repentance of His servant as long as he has not gurgled [i.e., is not on his deathbed]." And the Almighty's saying: "For those who do evil in ignorance" (Quran 4:17) encompasses both disbelief and sins. So, everyone who disobeys his Lord is ignorant until he repents.