Some good Wesleyans took an interest in the young gardener, and he attended their meetings, which he found very helpful.
When a little later on he was offered a much better situation on the condition that he gave up Methodism he refused it, preferring, as he says, "his God to white and yellow ore".
One day he went to Warrington, and whilst there saw a placard announcing a missionary meeting, at which the Rev. William Roby was to speak. The sight of this reminded him of the descriptions his mother used to read of mission work in Greenland, and the subject became fixed in his mind.
A little later he had the opportunity of hearing Mr. Roby, and determined to call upon him and offer himself for mission work.
So great was his dread of making this call that he asked a companion to accompany him, and be present at the interview, but could only induce his friend to wait for him outside.
When he got to Mr. Roby's door his courage failed him; he looked longingly at his friend and began to retreat. However, his conscience would not allow him to surrender; and back again he went to the house, but still feared to knock.
At length after walking up and down the street in a state of painful indecision he returned and ventured to knock. A terrible moment followed. He would have given anything to run away, and hoped with all his heart Mr. Roby would be out.
This, however, was not the case; and, brought face to face with the mission preacher, he told his story simply and effectively, and Mr. Roby promised to write to the Missionary Society about him.
At first the offer of his services was declined, but later on it was accepted; and on 30th September, 1816, he was ordained at Surrey Chapel. Amongst others set apart at the same time was John Williams, the martyr of Erromanga.
It was at first proposed that Williams and Moffat should go together to Polynesia; but Mr. Waugh remarked that "thae twa lads were ower young to gang together," so they were separated.