Doubt Regarding Ritual Purity

Question: If a man performs wudu' and then goes to pray, and he doubts his wudu' during the prayer or after it, what should he do?

Answer: If a person performs wudu' with certainty and completes his ritual purity, and then he experiences doubt afterwards as to whether his wudu' has been invalidated or not, he should not pay attention to this doubt; because he performed wudu' with certainty, and certainty is not removed by doubt;As he (peace and blessings be upon him) said:
, so certainty is not removed by doubt in ritual purity or in anything else.