The chest of Rasulullah [Sallallaahu Alayhi Wasallam] was split on four occasions:
1. When Rasulullah [Sallallaahu Alayhi Wasallam] was a child and under the guardianship of Halima al-Sa?diyyah. Rasulullah [Sallallaahu Alayhi Wasallam] was 4 years old at that time. Jibraaeel [Alayhis salaam] and Mikaaeel [Alayhis salaam] dressed in white came with a golden tray filled with ice and split open the chest of Rasulullah [Sallallaahu Alayhi Wasallam] and removed his heart and removed 1 or 2 blood clots. They mentioned that this was the Shaytaan, i.e. portion in man. Thereafter, they placed the heart in the tray and washed it with the ice and replaced the heart into its place.
2. When Rasulullah [Sallallaahu Alayhi Wasallam] was 10 years old.
3. When Rasulullah [Sallallaahu Alayhi Wasallam] received prophethood.
4. When Rasulullah [Sallallaahu Alayhi Wasallam] was taken on Me?raaj (heavenly ascension).
[ Seeratul Mustafa vol.1 pgs.73-84 ]
and Allah Ta’ala Knows Best
Mufti Ebrahim Desai