/You said that we are all evolving and progressing. But where did this whole process start? Was there a beginning?/
We came into existence from God's delight. When we entered the creation, we evolved through the lower stages: mineral life, plant life, animal life. Although we have now entered into the human life, we are still half animal. There are some who want to kill or hurt others, and exhibit all kinds of animal and destructive tendencies.
But in the case of a spiritual aspirant, it is different. He tries to transcend his lower nature and aspires to be aware of and live in his divine nature, where he experiences peace, joy and love.
/Why do you believe in rebirth? I know pretty well that I shall go to God when I die. And that's all./
My friend, as you will go to God when you leave the body, so will I. Let us be wise. Our business is to go to God; it is God's business if He wants to keep you in Heaven and send me back to earth. Or vice versa. The best thing for us is to surrender to God and let Him fulfill us in His own way. Having thrown aside all our preconceived ideas regarding the existence or non-existence of rebirth, let us do the only thing of importance: be one with His Will and Consciousness.
/When the soul is going to reincarnate, is it forced to do so or does the soul have the privilege of making this decision?/
When the soul leaves the body, it gradually goes back to its own region, after leaving the physical, vital, mental and psychic sheaths. Nobody can compel the soul to reincarnate, save the Supreme. The Supreme has the power to compel the soul, but He does not do it. The Supreme does not compel anybody to do anything. The soul has an inner urge to fulfill the Divine here on earth. Some souls want to take rest for a few years, say ten, twenty, forty or sixty years, while others who are not developed and are full of earthly desires, who want to fulfill their countless unfulfilled desires, come back to the physical world sooner. To be sure, they are not going to fulfill anything spiritual here on earth. They just come back to the world of manifestation to fulfill their countless human desires.
/How long do we have to continue to reincarnate?/
If one aspires, one expedites one's realization. Otherwise, an ordinary human being takes hundreds and hundreds of incarnations before actual realization takes place. Aspirants who consciously enter into the path of spirituality and try to discipline themselves on the strength of their inner cry will naturally gain their realization sooner than those who are still sleeping and are not yet conscious of the inner life.