Are all the conditions for repentance required simultaneously for it to be accepted, such as someone who regretted, desisted, and resolved not to return [to the sin] after a short period of doubt? Is his repentance valid? And is the repentance of an apostate accepted if he regrets, desists, and resolves, and then pronounces the two testimonies, or must he repent after pronouncing them?

It is not permissible to delay any of the pillars of repentance, because repentance is an immediate obligation, and delaying it is considered another sin that necessitates repentance. Indeed, Al-Izz ibn Abd al-Salam stated that repentance is an immediate obligation, and whoever delays it becomes disobedient by delaying it. His disobedience is repeated with the repetition of the times extended for it, which necessitates another repentance from the delay itself. If repentance is an immediate obligation, then its pillars—namely, remorse, determination not to return to the sin, and cessation from the sin—are all immediately obligatory, and repentance is not valid unless all of them are complete.