We know how this necessity of a rock-like foundation for a spiritual structure, and the possibility of finding such a foundation only in His own words and person, were illustrated by our Lord’s method in the foundation of His Church. A crowd came round Him at the first, offering Him the same kind of allegiance which men will give to spiritual teachers and benefactors in moments of enthusiasm. “Many believed on his name, beholding the signs which he did.” And our Lord stood strangely aloof from them. “He did not trust himself unto them,” St. John says, “for that he knew all men, and because he needed not that any should bear witness concerning man, for he knew of himself what was in man.”[87] So He tested the would-be disciples, till at last by His strange self-withdrawing ways, by His severe words, by His enigmatic utterances, He had sifted out those who were really in earnest in following Him from those who were not; exhibiting in all this a strange contempt for majorities or mere numbers. At last He had gathered round Him the little band of those who were really ready to follow and obey to the uttermost, the band of His apostles. Here were men who had indeed got down to the rock, and were building on it and nothing short of it. Here were men who could trust Him and His word, and take as the basis for their life the confession of His name. Therefore, like that on which they built, they were themselves rock-like, and not as the shifting sand of ordinary human nature. These then could be used as the foundations of Christ’s new society. So under circumstances where a special strain was put upon their loyalty, He asked the great question of the apostles; and Peter gave the great answer: “Thou art the Christ, the Son of the living God.” Then, as it were with a sigh of relief, our Lord turns upon him, and greets him with His supreme benediction, and recognizes in him――if not yet something which is ready to His hand, yet something which is capable of being made ready: “Blessed art thou, Simon Bar-Jonah: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven. And I also say unto thee, that thou art Peter――rock-man――and upon this rock I will build my church.”[88] Thus our Lord illustrated in His own practice what He teaches here. He would have men dig down to the rock, and build their spiritual fabrics there; and the rock is nothing else than His own person and His own word. To hear Him, and go away without imbibing His teaching and putting it into practice, to be nominally a Christian but in reality of the world, that is to build a house upon the sand. And the test of all spiritual fabrics is their capacity to stand the strain of wild and rough experiences. That is a formidable lesson for an age of rapid workmanship; an age which resents the necessity for underground work and silent preparation.