James 1:15

Then when lust hath conceived - Compare Job 15:35. The allusion here is obvious. The meaning is, when the desire which we have naturally is quickened, or made to act, the result is that sin is produced. As our desires of good lie in the mind by nature, as our propensities exist as they were created, they cannot be regarded as sin, or treated as such; but when they are indulged, when plans of gratification are formed, when they are developed in actual life, the effect is sin. In the mere desire of good, of happiness, of food, of raiment, there is no sin; it becomes sin when indulged in an improper manner, and when it leads us to seek that which is forbidden - to invade the rights of others, or in any way to violate the laws of God. The Rabbis have a metaphor which strongly expresses the general sense of this passage” - “Evil concupiscence is at the beginning like the thread of a spider’s web; afterwards it is like a cart rope.” Sanhedrin, fol. 99.

It bringeth forth sin - The result is sin - open, actual sin. When that which is conceived in the heart is matured, it is seen to be sin. The design of all this is to show that sin is not to be traced to God, but to man himself; and in order to this, the apostle says that there is enough in the heart of man to account for all actual sin, without supposing that it is caused by God. The solution which he gives is, that there are certain propensities in man which, when they are suffered to act themselves out, will account for all the sin in the world. In regard to those native propensities themselves, he does not say whether he regards them as sinful and blameworthy or not; and the probability is, that he did not design to enter into a formal examination, or to make a formal statement, of the nature of these propensities themselves. He looked at man as he is as a creature of God - as endowed with certain animal propensities - as seen, in fact, to have strong passions by nature; and he showed that there was enough in him to account for the existence of sin, without bringing in the agency of God, or charging it on him.

In reference to those propensities, it may be observed that there are two kinds, either of which may account for the existence of sin, but which are frequently both combined. There are, first, our natural propensities; those which we have as men, as endowed with an animal nature, as having constitutional desires to be gratified, and wants to be supplied. Such Adam had in innocence; such the Saviour had; and such are to be regarded as in no respect in themselves sinful and wrong. Yet they may, in our case, as they did in Adam, lead us to sin, because, under their strong influence, we may be led to desire that which is forbidden, or which belongs to another. But there are, secondly, the propensities and inclinations which we have as the result of the fall, and which are evil in their nature and tendency; which as a matter of course, and especially when combined with the former, lead to open transgression. It is not always easy to separate these, and in fact they are often combined in producing the actual guilt of the world. It often requires a close analysis of a man’s own mind to detect these different ingredients in his conduct, and the one often gets the credit of the other. The apostle James seems to have looked at it as a simple matter of fact, with a common sense view, by saying that there were “desires” (ἐπιθυμίας epithumias) in a man’s own mind which would account for all the actual sin in the world, without charging it on God. Of the truth of this, no one can entertain a doubt. - (See the supplementary note above at James 1:14.)

And sin, when it is finished bringeth forth death - The result of sin when it is fully carried out, is death - death in all forms. The idea is, that death, in whatever form it exists, is to be traced to sin, and that sin will naturally and regularly produce it. There is a strong similarity between this declaration and that of the apostle Paul Romans 6:21; and it is probable that James had that passage in his mind. See the sentiment illustrated in the notes at that passage, and Romans 5:12 note. Any one who indulges in a sinful thought or corrupt desire, should reflect that it may end in death - death temporal and eternal. Its natural tendency will be to produce such a death. This reflection should induce us to check an evil thought or desire at the beginning. Not for one moment should we indulge in it, for soon it may secure the mastery and be beyond our control; and the end may be seen in the grave, and the awful world of woe.