A detailed philological and historic-cultural analysis of the legend of the first fratricide (Gen 4: 1-17) shows that this legend originated at the point of divergence of the two great types of economy: the archaic cattle – breading and the vising agricultural one; the legend reflects in a very specific way the negative attitude of the former cattle – breeders to the change in their traditional mode of life. This interpretation makes at last clear the use of some terms and expressions which have been declared hopelessly corrupted, and a reason for seemingly irreconcilable contradictions in the text is suggested. Thus contrary to the common. Opinion of scholors, it appears to be in order and correct.