How sound is the shaykh’s claim that the Companions of the Prophet (peace be upon him) used to take out his heart to clean it with Zamzam water and then return it, and to what extent is his statement sound that the Prophet (peace be upon him) used to starve himself to bring benefit to the Ummah?

It was not reported from the noble Companions that they washed the heart of the Prophet, peace and blessings be upon him, with Zamzam water. Rather, it was the incident of "the splitting of the chest" which occurred twice at the hands of the angels. The wisdom behind it was to remove the portion of Satan from his heart and fill it with wisdom and faith, and this is from the realm of the unseen. As for the saying that he, peace and blessings be upon him, used to go hungry to satiate others, and thirsty to quench the thirst of others, this has not been reported in the Sunnah. What is mentioned in the Prophetic biography are his miracles in multiplying food to feed the people, and that months would pass over his house with nothing in it but dates and water. This differs from the false doctrine of redemption held by Christians, which is based on erroneous ideas such as the inheritance of sins and the necessity of sacrifice to atone for sins.