2. The most usual cause of inward darkness is sin of one kind or another. This it is which generally occasions what is often a complication of sin and misery. And, _first_, Sin of _commission_. This may frequently be observed to darken the soul in a moment: especially if it be a known, a wilful or presumptuous sin. If for instance, a person who is now walking in the clear light of God’s countenance, should be any way prevailed on to commit a single act of drunkenness or uncleanness, it would be no wonder if in that very hour he fell into utter darkness. It is true, there have been some very rare cases, wherein God has prevented this, by an extraordinary display of his pardoning mercy, almost in the very instant. But in general, such an abuse of the goodness of God, so gross an insult on his love, occasions an immediate estrangement from God, and a _darkness that may be felt_. 3. But it may be hoped, this case is not very frequent; that there are not many who so despise the riches of his goodness, as while they walk in his light, so grosly and presumptuously to rebel against him. That light is much more frequently lost, by giving way to sins of _omission_. This indeed does not immediately quench the Spirit, but gradually and slowly. The former may be compared to pouring water upon a fire: the latter to withdrawing the fewel from it. And many times will that loving Spirit reprove our neglect, before he departs from us. Many are the inward checks, the secret notices he gives, before his influences are withdrawn. So that only a train of omissions wilfully persisted in, can bring us into utter darkness. 4. Perhaps no sin of omission more frequently occasions this, than the neglect of private prayer; the want whereof cannot be supplied by any other ordinance whatever. Nothing can be more plain, than that the life of God in the soul does not continue, much less increase, unless we use all opportunities of communing with God, and pouring out our hearts before him. If therefore we are negligent of this, if we suffer business, company, or any avocation whatever, to prevent these secret exercises of the soul, (or which comes to the same thing, to make us hurry them over in a slight and careless manner) that life will surely decay. And if we long or frequently intermit them, it will gradually die away.