On Sunday, December 11th (1932), Meher Baba discoursed about reincarnation, explaining what spirit means:
The soul always remains the same; it is only the spirit which reincarnates and takes successive possession of bodies. People do not understand what spirit is and only vaguely use the term. There are so many terms used for one aspect.
The soul is infinite, everlasting and pure. At present, you do not realize the soul, and your mind means everything to you. Yet the mind is not you, but what clothes are to the body. You are not the mind that feels and experiences everything. You are not the ego – you are the soul.
Until it is realized, the spirit has to reincarnate and change bodies. You change your clothing when it becomes old and so it is with the body. You all have had so many bodies, yet your soul never changes. It is the spirit which reincarnates again and again until you get back to the Source of all – which is Baba!
Lord Meher, Original Publication, Bhau Kalchuri, Vol. 5, p. 1746.