There was only one time, I am told, that Edinburgh Castle was ever taken by the enemy, and that was done by climbing on the back rocks. The rocks were so steep the besieged did not believe the enemy could get in that way, but that was just where they got in. I used to think when I had been a Christian ten or twelve years I should be so strong that there would be no danger of my ever being tempted, but I find that I was blind. I have more temptations now than I ever had before, and it takes twenty times as much grace to keep me now as at first. Let every man take heed, lest he fall. We can not tell how quickly we may fall if we are not kept by the grace of God. Peter had to learn this lesson before he went out to preach to others. He was kept by the grace of God, if he could not keep himself. Well, I have got right here two faults of the apostle. When the Lord told him he should deny Him thrice, he ought to have trembled and cried: “Lord, keep me from denying Thee!” But, no! He said: “Lord, I am not going to deny You, if the rest do.” Just see where he stands. He stands on a slippery place, and it will not be long before he will be down. Self-confidence leads many men to their fall. We must keep very humble and keep our eyes on the Master, and see that we do not go to sleep. If we do get asleep, then it won’t be long before we deny Him. And so we find that when Christ was down in the garden, sweating great drops of blood, He knew He was hastening to death on the cross. Peter went to sleep. And when Jesus came back He said: “Why sleep ye? Rise and pray, lest ye enter into temptation.” Peter had been with the Lord three years, but he had to sleep. The next that happens, for that second step down, we find that Peter fights in the flesh. When they came to arrest Christ, Peter took out his sword and cut off the servant’s ear. That servant was the only person who had suffered through the followers of Christ up to that time. Peter cut the ear off, but it did not stay off long, for it got back in just about five minutes. Jesus cried out: “Peter, put up your sword. If I wanted to defend Myself, I could call seventy thousand angels down; I could call legions of angels down; I could defend Myself if I wanted to.” But, no; He did not do that. He had to rebuke Peter, to put a thorn in his flesh. The next thing Peter did was to follow Jesus afar off; that is the next step. When a man gets away from the Savior, then it won’t be long before he follows Him afar off. You know Peter said, at first, he would keep close to Him. “I will stand by You; I am willing to die with You,” he had said. But now Peter changed his mind, and he followed Jesus afar off. Well, the next thing, we find that Peter is in bad company. That is another step down. He had got, by this time, down pretty low. A young lady comes in, looks at Peter, and says: “This man is one of His disciples.” “No, I am not; no, not I,” says Peter.