If a person performs an action without prior intention, then remembers during or after the action the possibility of it being counted as a reward, is he permitted to intend for this action to be counted as a reward from Allah? And is it sufficient to form the intention for reward during or after performing ghusl from janabah, and will his reward be the same as someone who intended from the beginning? And is it permissible for someone who performed an action out of showing off, then repented, to still count the reward for the effect of that action?

"Ihtisab" (seeking reward from God) is the intention of gaining reward and seeking Allah's pleasure. It is the ultimate goal of righteous deeds, while faith is the motive for action. A Muslim may perform a deed purely for the sake of Allah without consciously intending "ihtisab," and they will be rewarded for it. The reward is greater if the intention of "ihtisab" is added. For good deeds that benefit others, the doer is rewarded even if they did not have an explicit intention at the time of the action. As for obligatory deeds, one is rewarded for them with the intention of fulfilling an obligation. One is not rewarded for intending "ihtisab" after the completion of the deed.