His stay in Ayton was a very happy one.  He liked his work, and had several warm friends in the village and district.  Among these were Mr. Ure, the kindly old minister who had married his parents and baptized himself.  Then there was Mr. Stark, minister of another Secession church in the village—­a much younger man than Mr. Ure, but a good scholar and a well-read theologian.  There was also a fellow-student, Henry Weir, whose parents lived in Berwick, and who used often to walk out to Ayton to see him, Cairns returning the visits, and seeing for the first time, under Weir’s auspices, the old Border town in which so much of his own life was to be spent.

All this while he was working hard at his private studies.  To these studies he gave all the time that was not taken up by his teaching.  He read at his meals, and so far into the night that his aunt became alarmed for his health.  He worked his way through a goodly number of the Greek and Latin classics, in copies borrowed from the libraries of the two ministers; and he not only read, but analysed and elaborately annotated what he read.  But in the notes of the books read during the year 1837 a change becomes evident.  It can be seen that he took more and more to the study of theology and Christian evidences, and his note-books are full of references to Baxter and Jeremy Taylor, to Robert Hall, Chalmers, and Keith.

At length in the summer a crisis was reached.  A letter to his father, which has not been preserved, announced that his views and feelings with regard to spiritual things had undergone a great and far-reaching change, and that religion had become to him a matter of personal and paramount concern.  Another letter to Henry Weir on the same subject is of great interest.  It is written in the unformed and somewhat stilted style which he had not yet got rid of, and, with characteristic reticence, it deals only indirectly with the details of the experience through which he has passed, being in form a disquisition on the importance of personal religion, and a refutation of objections which might occur to his correspondent against making it the main interest of his life.

“My dear Henry,” the letter concludes, “I most earnestly wish that you would devote the energies of your mind to the attentive consideration of religion, and I have no doubt that, through the tuition of the Divine Spirit, you would speedily arrive at the same conviction of the importance of the subject with myself, and then our friendship would, by the influence of those feelings which religion implants, be more hallowed and intimate than before.  I long ardently to see you.”

The experience which has thus been described caused no great rift with the past, nor did it produce any great change in his outward life.  He did not dedicate himself to the ministry; he did not, so far as can be gathered, even become a member of the Church; and although for a short time he talked of concentrating his energies on the Greek Testament, to the disparagement of the Greek and Latin classical writers, within two months we find him back at his old studies and strenuously preparing for the coming session at College.  But a new power had entered into his life, and that power gradually asserted itself as the chief and dominating influence there.