Noah's sin brings before us two facts about sin. First, that the smaller temptations are often the most effectual. The man who is invulnerable on the field of battle amidst declared and strong enemies falls an easy prey to the assassin in his own home. When all the world was against him, Noah was able to face single-handed both scorn and violence, but in the midst of his vineyard, among his own people who understood him and needed no preaching or proof of his virtue, he relaxed. He was no longer in circumstances so difficult as to force him to watch and pray, as to drive him to God's side. The temptations Noah had before known were mainly from without; he now learnt that those from within are more serious. Many of us find it comparatively easy to carry clean hands before the public, or to demean ourselves with tolerable seemliness in circumstances where the temptation may be very strong but is also very patent; but how careless are we often in our domestic life, and how little strain do we put upon ourselves in the company of those whom we can trust. What petulance and irritability, what angry and slanderous words, what sensuality and indolence could our own homes witness to! Noah is not the only man who has walked uprightly and kept his garment unspotted from the world so long as the eye of man was on him, but who has lain uncovered on his own tent-floor. Secondly, we see here how a man may fall into new forms of sin, and are reminded especially of one of the most distressing facts to be observed in the world, viz., that men in their prime and even in their old age are sometimes overtaken in sins of sensuality from which hitherto they have kept themselves pure. We are very ready to think we know the full extent of wickedness to which we may go; that by certain sins _we_ shall never be much tempted. And in some of our predictions we may be correct; our temperament or our circumstances may absolutely preclude some sins from mastering us. Yet who has made but a slight alteration in his circumstances, added a little to his business, made some new family arrangements, or changed his residence, without being astonished to find how many new sources of evil seem to have been opened within him? While therefore you rejoice over sins defeated, beware of thinking your work is nearly done. Especially let those of us who have for years been fighting mainly against one sin beware of thinking that if only _that_ were defeated we should be free from sin. As a man who has long suffered from one bodily disease congratulates himself that at least he knows what he may expect in the way of pain, and will not suffer as some other man he has heard of does suffer; whereas though one disease may kill others, yet some diseases only prepare the body for the assault of worse ailments than themselves, and the constitution at last breaks up under a combination of ills that make the sufferer a pity to his friends and a perplexity to his physicians.