Jewish teachers of first-century Israel lacked the sophisticated methods of mass communication we have today. Consequently, the sages of Jesus’ day spent much of their time traveling throughout the country, much like the biblical prophets, to communicate their teachings and interpretations of Scripture.
The original understanding of the third commandment, “You shall not take the name of the LORD your God in vain” (Exod. 20:7), was that one must keep one’s vows when swearing by God’s name. Israel’s ancient sages eventually came to interpret this commandment to mean using the LORD’s name lightly or frivolously. To avoid the risk of employing the divine name irreverently, the sages ruled that one should not utter it at all.