Moreover, it is evident that the spiritual revelation which is in part recorded in the Bible was not limited to the Israelitish race or to the twelve centuries represented by the Old and New Testaments. The biblical writers themselves assume this fact. According to the early Judean prophetic narratives, Enoch, who lived ages before Abraham and Moses, was a worshipper of Jehovah (Gen. iv. 26). Cain and Abel are both represented in the familiar story of Genesis iv., as bringing their offerings to Jehovah. One of the chief teachings of the earliest stories in the Old Testament is that men from the first knew and worshipped God and were held responsible for their acts according to their moral enlightenment. History, science, and the Bible unite in testifying that the revelation of spiritual truth to mankind was something gradual, progressive, and cumulative; also that it is dependent upon the ability of men to receive it. This capacity of the individual to receive is, after all, the determining factor in the process of divine revelation; for God's truth and his desire to impart it are always the same. Hence, whenever conditions favor, or national or private experiences clarify the vision of a race or group of men, a revelation is assured. [Sidenote: _Antiquity of human civilization and religion_] In the light of ancient history and the result of recent excavations it is possible, now as never before, to study the varied influences and forces employed by God in the past to open the spiritual eyes of mankind to see him and his truth. The geological evidence suggests that man, as man, has lived on this earth, fifty, perhaps one hundred thousand years. Anthropology, going farther back than history or primitive tradition, traces the slow and painful stages by which early man learned his first lessons in civilization and religion. From the beginning, man's instincts as a religious being have asserted themselves, crude though their expression was. The oldest mounds of Babylonia and Egypt contain ruins of ancient temples, altars, and abundant evidence of the religious zeal of the peoples who once inhabited these lauds. The earliest examples of human literature thus far discovered are largely religious in theme and spirit. [Sidenote: _Primitive unfolding of the innate religious instinct_]