The Source is the Universe, the source of all life in the Universe. But I think this thing about people having souls is back asswards. Souls have people. Souls can have many different bodies in many different time frames, all of which are here to experience life to the fullest to add to the overall experience of the Source. Eventually all souls return to the Source from whence they came. It has been said that people are spiritual beings having a human experience and that people are the eyes and ears of god experiencing life on Earth. Religion has been keeping the knowledge of our true nature from us in order to control us, because if we knew how god like, how creative we really are, we would not need religion or control.
Every spiritual, religious and philosophical book I read lead me to the inevitable conclusion that we are our own gods and goddesses, that we create our own reality and that all the spiritual practices in the world were designed to bring us to that knowledge. Religion is a lie, God, heaven and hell are lies. Heaven and hell are what we make of our lives. All the holy books were written as metaphors for life. They were never meant to be taken literally. Taking them literally is the lie of religion.
Religious and spiritual books are fingers pointing the way back to the Source. But most people stop and suck on them for nourishment instead of going in the way they are pointing.