Is the reward of one who prays sitting due to an excuse the same as the reward of one who prays standing?

Question:
Is the reward that follows, O Shaykh, for the one who prays sitting the same as that of the one who stands, if he has circumstances and pain in the joints of his back?

Answer:
Yes, if he leaves off standing in the obligatory prayer due to an excuse, if he leaves off standing in the prescribed prayer due to an excuse, then he has the same reward as the one who stands, because he did not leave off standing except for an excuse, and the one who has an excuse, if his intention is sound, then he attains the reward of the one who has no excuse in worship and action, and this is from the favor of Allah (Glorified and Exalted is He). This is in the obligatory prayer. As for the voluntary prayer, if he has an excuse and prays sitting, then he has the full reward, and if he prays while he is able to stand, then this is permissible and he has half the reward, half the reward of the one who stands. Yes.