Marriage was always recommended to the missionaries of the Baptist Societies, and Williams's fate was no sooner decided than he chose Mary Channer, a constant attendant at the Tabernacle, and a woman helpful, kind, and brave, as befitted a missionary's wife.
A great meeting was soon after held, as a sort of dedication of the new labourers, nine in number, who were thence to go forth,--five to South Africa, four to Polynesia.

Among the Africans was Robert Moffat, a name memorable, both on his own account and as the father-in-law of Livingstone.

An elderly minister stood forth and questioned the young men in the face of the congregation on their faith, their opinions, their motives, and their intentions; and then a Bible was solemnly presented to each by an elder minister, John Angell James, of Birmingham, one of the most able and highly reputed Nonconformists then living; and another minister, Dr.Waugh, addressing himself to Williams, who was much the youngest of the nine, said, "Go, my dear young brother, and if your tongue cleave to the roof of your mouth, let it be with telling poor sinners the love of JESUS CHRIST; and if your arms drop from their shoulders, let it be with knocking at men's hearts to gain admittance for Him there." The impression never left John Williams, and the injunction was fulfilled to the utmost of his power.

He was a man of strong and vigorous frame, well fitted to encounter the perils of climate; and with much enterprise, hardihood, and ingenuity.

That his mind was in some degree narrowed by want of education, perhaps mattered less in the peculiar field of his labours, where he was seldom brought in contact with wide questions.