Islam believes in the principle of saving human lives. In one article, Islamic Views on Organ Transplantation, it says: “...the majority of the Muslim scholars belonging to various schools of Islamic law have invoked the principle of priority of saving human life and have permitted organ transplantation as a necessity to procure that noble end.” 
In the name of Allah, most Gracious, most Merciful 
“He whoever saves a life, it is as if he saved all mankind.” 
(Holy Qur’an 5:32) 
A Shariah Fatwa by eminent Islamic scholar, Dr. Sheikh Yusuf Al-Qaradawi can be found below. 
Christianity believes that the Lord demonstrated with his own life how, even in sorrow, love enables them to embrace the needs of others. The decision to donate organs to save the lives of others after death is the beginning of healing for many.
According to Judaism, “If one is in the position to donate an organ to save another’s life, it’s obligatory to do so, even if the donor never knows who the beneficiary will be.”
Buddhists believe that organ and tissue donation is a matter of individual conscience, and they place high value on acts of compassion.
Hindus are not prohibited by religious law from donating their organs. This act is an individual’s decision. There is nothing in the Hindu religion indicating that part of a human, dead or alive, cannot be used to alleviate the suffering of other humans.