The modern theistic movement first found definite expression and impetus in the life and teaching of that noble son of India, Ram Mohan Roy, who hailed from the Brahmanic aristocracy of Bengal. He was born in 1774—just before the birth of American Independence. He studied well the ancient writings of Hinduism and translated some of the most important into English. He also searched eagerly and enthusiastically the Christian Scriptures; for which purpose he made himself familiar with the Greek and Hebrew languages. So mightily did the New Testament and its precepts grip him that he wrote and published, in 1819, an excellent tract, "The Precepts of Jesus the Guide to Peace and Happiness." This is a remarkable testimony to the ethical preëminence of the Bible. He later declared that he "believed in the truths of the Christian religion."

Being unwilling to abide alone in this discovery and in these convictions, he established, in 1815, the "Atmâ Sabhâ," or "Soul Society," in his own home. This soon developed into a small church, for which a suitable edifice was erected, that they might worship the one God free from the contaminating influence of popular idolatry and Hindu ceremonial.

This truly great man, without the aid of any European missionary, in the quiet solitude of his own heart, and under the influence of the Spirit of God, rose to some of the highest truths of Theism, and, under the mighty influence of Christian literature, became a reformer of the first order among his people.

But, during a visit to England he sickened, and died in 1833; and the theistic movement weakened and waned for a few years, deprived of his leadership and inspiring presence.

It was in 1843 that the Brahmo Somaj of Ram Mohan Roy was united with another Sabha organized by another great soul, Debendra Nath Tagore. Under the guidance of this sturdy reformer, the Brahmo Somaj movement put on new life and energy. Debendra Nath was very devout and courageous. He was opposed to the religion of his fathers, as practised by the people. Nevertheless, he was somewhat anchored to the past. He still clung to the Hindu scriptures and regarded the Vedas as infallible. Later, however, as these Hindu writings were studied with more care, his faith in them was considerably shattered, and he began to deny their supreme authority.

He and the other members of the society here entered upon a great struggle which ushered them into an "Age of Reason." The Vedas were abandoned as an ultimate authority, and the Brahmo Somaj, for a time, became "a Church without a Bible," and without any anchorage but the higher reason of its members.

In 1852, the society was reorganized. Reason was soon found to be inadequate as the foundation of faith; and they passed on to an intuitional basis. That again seemed to be even more unsatisfactory than reason itself. After a few years, the movement gradually developed a doctrine of inspiration, when the utterances of the leaders themselves were regarded as inspired and became the voice of God to the members. Thus, within a few years, Brahmo Somaj moved almost in a circle, in its search for a stable anchorage to its faith; and it returned to a point dangerously near to the Hindu position which it had left a few years before.

The rapid movement above indicated was chiefly owing to an ardent youth, who rallied to the support of Debendra Nath, and who gradually took the reins into his own hands. This young man was Keshub Chunder Sen; and he soon became the leading figure, certainly the most striking, in the whole theistic movement of India. He acquired growing influence over Debendra Nath, became the controlling spirit, and continued until his death to be the central figure of Theism in India.

Chunder Sen was a great enthusiast, full of intellectual resource, and, withal, a man of deep spirituality. He was an Oriental of the Orientals; his mind was of a thoroughly mystic type, and, like the devout Hindu, he loved the rigours of asceticism, and, in not a few instances, yielded to the fascinations of the methods of the Yogi.

He was a restless soul. Hinduism had so much that was repulsive to him; and he felt that polytheism and idolatry had so crushed out of his people all the beauty of a living faith that he longed to hasten communication of his message of truth and of life the new and glorious day of Theism for India. His pace was so much faster than that of Debendra Nath that it took but a few years to make their separation a necessity. This took place in 1865. Thereupon, the old society became known as the "Âthi Somaj,"—"The Original Somaj,"—while Sen and his party formed a new organization, which was pretentiously known as "The Brahmo Somaj of India." This happened in 1866.