Jonas is named as one of the twelve disciples Jesus Christ chose during his ministry to the Nephites after his resurrection. He appears in the roster of the twelve in 3 Nephi 19:4, listed among Nephi, Timothy, Jonas, Mathoni, Mathonihah, Kumen, Kumenonhi, Jeremiah, Shemnon, Zedekiah, and Isaiah. The record gives no parentage or other relationship for this Jonas; the name occurs twice in the list, the first instance being Nephi’s son and this second instance standing without further identification (3 Nephi 19:4).
When the multitude gathered the next day, the twelve divided the people into twelve groups, taught them, and had them kneel and pray to the Father in the name of Jesus. The disciples then prayed for the Holy Ghost, went to the water’s edge, and were baptized by Nephi, after which the Holy Ghost fell upon them (3 Nephi 19:5-13).