Religion

Religion is discipline of life. From time immemorial,religious priests have been preaching for restraining from material lusts  in 'Kanchan & Kamini". Thus necessarily the imagination of reward and punishment according to good and evil deeds  of mankind were preached. A network of religions came into being and the religion became part and parcel of life. The intelligent class of people in the society wrote verses, mantras for example the Gaitri mantra that became very important.
It is really remarkable that all the religions of the world have denounced the material pleasures and have given priority to spiritual pleasures. The hermit Basistha was the Guru of King Dasaratha .If Basistha liked, he could have got all material lusts and pleasures from King Dasaratha. But instead of this , he used to live in a hut in the jungle and used to live on milk and roots of plants.
Now the question arises asto why Basistha led a life of austerity and penance.? The answer is clear. Pious and auster life used to give him communion with infinitum which in turn have a perrenial source of pleasure and that pleasure was hundreds and thousands of time more pleasant than the material pleasure. A simple example of this is seen every where. When a child is fed by the mother, the meal goes to the stomach of the child,but the mother becomes overjoyed. This is a spiritual pleasure  that is the pleasure of feelings.
By and large the concept of the Almighty God whom the Islamic religion says Allah was evolved. The writing of the four Vedas also came into being and the omniscient, omnipresent and omnipotent and all pwerfulness of God was accepted by all religions. Thus it is crystal clear that religion evolved in India in contexts with spiritualism.
In Bhagwat Geeta Lord Krishna exclaims that there is no God save Him. Similar concept is also there in  other religions. According to Geeta the soul changes new clothes,the old and worn out ones are left out,the soul is immortal.
Thus if we  read Indian religious books closely we find that there is no difference among various religious sects.When there is God and only God who is all powerful,what are the various dieties like Durga, Kali etc. ?

They are only the manifestations of the all-powerful God who is both in form and without form.
Various incarnations of God like Sri Rama, Sri Krishna Sri Budha,Sri Mahavira, Sri Chaitanya and Sri Ramakrishna have from time to time preached the same concept.

Thus we find that the Indian religion has gone through the various processes of evolution and has emerged with a strong base of spiritualism.