Once a week during the session a party of six or eight students came to tea at Spence Street, until the whole of his two classes had been gone over. After tea in the otherwise seldom used dining-room of the house, some of the party accompanied the professor to the study. Here he would show them his more treasured volumes, such as his first edition of Butler, which he would tell them he made a point of reading through once a year. Others, who preferred a less unclouded atmosphere, withdrew with his brother into his sanctum. Soon all reassembled in the dining-room, and a number of hymns were sung--some of Sankey's, which were then in everybody's mouth, some of his favourite German hymns with their chorals, which might suggest references to his student days in Berlin or to later experiences in the Fatherland, and some by the great English hymn-writers. At last came family worship, always impressive as conducted by him, but often the most memorable feature by far in these gatherings. It was a very simple, and may seem a very humdrum, way of spending an evening; but the homely hospitality of the household--the conversational gifts, very different in kind as these were, of himself and his brother--and, above all, his genial and benignant presence, made everything go off well, and the students went away with a deepened veneration for their professor now that they had seen him in his own house. During his first two years in Edinburgh he was busily engaged in writing lectures and in adapting his existing stock to the requirements of the new curriculum. Of these lectures, and of others which he wrote in later years, it must be said that, while all of them were the fruit of conscientious and strenuous toil, they were of unequal merit, or at least of unequal effectiveness. Some of them, particularly in his Apologetic courses, were brilliant and stimulating. Whenever he had a great personality to deal with, such as Origen, Grotius, or Pascal, or, in a quite different way, Voltaire, he rose to the full height of his powers. His criticisms of Hume, of Strauss, and of Renan, were also in their own way masterly. But a course which he had on Biblical Theology seemed to be hampered by a too rigid view of Inspiration, which did not allow him to lay sufficient stress on the different types of doctrine corresponding to the different individualities of the writers. And when, after the death of Principal Harper, he took over the entire department of Systematic Theology, his lectures on this, the "Queen of sciences," while full of learning and sometimes rising to grandeur, gave one on the whole a sense of incompleteness, even of fragmentariness. This impression was deepened by the oral examinations which he was in the habit of holding every week on his lectures.