The total prohibition of oaths (Mt. 5.34-37) come from the historical Jesus. The criterion of discontinuity argues that there is no parallel to Jesus' total prohibition of oaths in the Jewish Scriptures, the intertestamental literature prior to 70 CE, or the New Testament. The Jewish Scriptures take oaths for granted and impose them in a few cases. Apart from Jas 5.12, the New Tetsament knows of no prohibition; Paul uses oaths with abandon. The criterion of multiple attestation argues that Jas 5.12 represents an independent tradition of the prohibition; Jas 5.12 is parallel to Mt. 5.34-37 in both content and structure; James has other examples of Jesus' sayings woven into his epistle without attribution; and Jas 5.12 is at odds with James's treatment of the Law in the rest of his epistle. Hence Jas 5.12 qualifies as an independent witness to an isolated stream of oral tradition preserving Jesus' prohibition. This is Part 1 of a two-part essay.