His action sermon, _i.e._ the sermon preached before the Communion, was always specially memorable and impressive. He had the subject chosen weeks, and sometimes even months, beforehand, and, as he had no other sermon to write for the Communion Sunday, he devoted the whole of the preceding week to its preparation. His action sermons, which were those he usually preached on special occasions when he was away from home, dealt always with some theme connected with the Person or Work of Christ. They were frequently apologetic in their conception and structure, full of massive argument, which he had a remarkable power of marshalling and presenting so as to be understood by all; but the argument, reinforced by bursts of real eloquence, always converged on the, exaltation of the Redeemer. "I never thought so much of him as I do to-day," said one of his hearers to another after one of these sermons, "I never thought so much of Christ as I do to-day," replied the other; and that reply showed that in at least one case the purpose of the preacher in preparing and delivering his sermon had been fulfilled. On the Sunday evening Cairns had a Bible-class of over one hundred young men and women, to which he devoted great care and attention. "It was the best hour of the day to us," wrote one who was a member of this class. "He was nearer us, and we were nearer him, than in church. The grandeur and momentum of his pulpit eloquence were not there, but we had instead a calm, rich, conversational instruction, a quiet disclosure of vast stores of information, as well as a definite dealing with young hearts and consciences, which left an unfading impression." But Cairns was no mere preacher and teacher. He put out his full strength as truly in his pastoral work as in his work for and in the pulpit. He visited his large congregation statedly once a year, offering prayer in each house, and hearing the children repeat a psalm or portion of Scripture which he had prescribed the year before. He timed these visits so accurately that he could on one occasion banter one of his elders on the fact that he had received more than his due in one year, because the last visitation had been on the 1st of January and this one was on the 31st of December. A good part of his visiting had to be done in the country, because a considerable section of his congregation consisted of farmers or hinds from Northumberland, from the "Liberties of Berwick," and even from Scotland, which first begins three miles out from the town. These country visitations usually concluded with a service in a barn or farm-kitchen, to which worshippers came from far and near.