There is no set number, but the number is very large:
[The Buddha said:] “What do you think, monks: Which is greater, the tears you have shed while transmigrating and wandering this long, long time — crying and weeping from being joined with what is displeasing, being separated from what is pleasing — or the water in the four great oceans?”
“As we understand the Dhamma taught to us by the Blessed One, this is the greater: the tears we have shed while transmigrating and wandering this long, long time — crying and weeping from being joined with what is displeasing, being separated from what is pleasing — not the water in the four great oceans.”
"Excellent, monks. Excellent. It is excellent that you thus understand the Dhamma taught by me.
“This is the greater: the tears you have shed while transmigrating and wandering this long, long time — crying and weeping from being joined with what is displeasing, being separated from what is pleasing — not the water in the four great oceans.”
– Assu sutta, Samyutta Nikaya 15.3
The continuation of the causal chain of which you are part. What you are now is the sum of many past causes. Unresolved causes will cause you to continue into the future. Someone who has attained nirvana no longer creates any new causes to be resolved, and so the chain ceases on death rather than continues into a subsequent life.
rossum
Is it possible that the Buddhist teaching of birth and re-birth is related to a spiritual birth and re-birth?
This concept can be found in the Christian “forgiving of sins” where you are as one dead, burdoned with sin, and ask God forgives the sin through the priest, one is “re-born”?
This concept can also be found in Islam where it is said: “O My slaves! You sin morning and evening and I forgive all your sins. So call on Me, I’ll forgive you all your sins.” where the need for a human intermediary for sin is eliminated?
This concept can be found in the Baha’i Faith where it is said: “O SON OF BEING! Bring thyself to account each day ere thou art summoned to a reckoning; for death, unheralded, shall come upon thee and thou shalt be called to give account for thy deeds.” where the individual is expected to undergo constant self-reflection (birth and re-birth) in order to overcome ones own shortcomings and power ahead on the path of constant advancement and spiritual improvement?
Nirvana is taught in ALL religions.
As we aspire and work and strive towards a sin-less existence through our own processes of birth and re-birth (on a spiritual level), our ego (self) is quashed, and its consciousness is dampened and we become eternally conscious of the Selfless One (Father, Absolute, God, Allah)
Attributes of the self (ego) include prejudice, desire, lust, greed, hatred, injustice, irreverence etc etc
Attributes of the selfless (spirit) include universal love, unity, generosity, justice, reverence, contemplation, service etc etc
Through the process of action, reflection, study (knowledge), action, reflection, study etc etc, one can be eternally born and re-born in this physical existence, as spiritual beings, striving towards Nirvana, and the loss of the consciousness of self.