Sahih Muslim Book 032, Hadith Number 6184.

Chapter : Politeness towards parents and their right to it.

Abdullah b. 'Anir reported that a person came to Allah's Apostle (may peace be upon him) and sought permission (to participate) in Jihad, whereupon he (the Holy Prophet) said: Are your parents living? He said: Yes. Thereupon he (the Holy Prophet) said: You should put in your best efforts (in their) service.

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