Does the supplication of the oppressed against the oppressor, that the oppressor not enter Paradise—if the oppressor is a Muslim and performs acts of worship—prevent him from entering Paradise?

The supplication of the oppressed is answered, for the Prophet, peace and blessings be upon him, said: "Beware of the supplication of the oppressed, for there is no barrier between it and Allah." However, among the impediments to its acceptance is for the oppressed to supplicate with sin or severance of kinship ties, such as supplicating against his oppressor with something greater than the injustice done to him. For supplication is retribution. If he supplicates, for example, that the oppressor be deprived of Paradise, this would be an transgression, and thus his supplication would not be answered. It is permissible for him to supplicate with something equivalent to the injustice he suffered, based on the Almighty's saying: "And the recompense of an evil deed is an evil deed like it." However, it is better for the oppressed to be patient and forgive, based on the Almighty's saying: "But whoever is patient and forgives - indeed, that is of the matters [requiring] strong determination."