(4) Side by side with "He sealed us," the Apostle writes, "He gave the earnest of the Spirit in our hearts." After what has been said, it is obvious that this is another aspect of the same thing. We are sealed with the Spirit, and we get the earnest of the Spirit. In other words, the Spirit is viewed in two characters: first, as a seal; and then as an earnest. This last word has a very ancient history. It is found in the Book of Genesis (xxxviii. 18: עֵרָבוׄן), and was carried, no doubt, by Phœnician traders, who had much occasion to use it, both to Greece and Italy. From the classical peoples it has come more or less directly to us. It means properly a small sum of money paid to clench a bargain, or to ratify an engagement. Where there is an earnest, there is more to follow, and more of essentially the same kind--that is what it signifies. Let us apply this now to the expression of St. Paul, "the earnest of the Spirit." It means, we must see, that in the gift of this Spirit, in that measure in which we now possess it, God has not given all He has to give. On the contrary, He has come under an obligation to give more: what we have now is but "the firstfruits of the Spirit" (Rom. viii. 23). It is an indication and a pledge of what is yet to be, but bears no proportion to it. All we can say on the basis of this text is, that between the present and the future gift--between the earnest and that which it guarantees--there must be some kind of congruity, some affinity which makes the one a natural and not an arbitrary reason for believing in the other.
But the Corinthians were not limited to this text. They had St. Paul's general teaching in their minds to interpret it by; and if we wish to know what it meant even for them, we must fill out this vague idea with what the Apostle tells us elsewhere. Thus in the great text in Ephesians (i. 13 f.), so often referred to, he speaks of the Holy Spirit with which we were sealed as the earnest _of our inheritance_. God has an "inheritance" in store for us. His Spirit makes us sons; and if sons, then heirs; heirs of God, joint-heirs with Christ. This connexion of the Spirit, sonship, and inheritance, is constant in St. Paul; it is one of his most characteristic combinations. What then _is_ the inheritance of which the Spirit is the earnest? That no one can tell. "Eye hath not seen, nor ear heard, neither have entered into the heart of man, the things that God hath prepared for them that love Him." But though we cannot tell more precisely, we can say that if the Spirit is the earnest of it, it must be in some sense a development of the Spirit; life in an order of being which matches the Spirit, and for which the Spirit qualifies. If we say it is "glory," then we must remember that only Christ in us (the seal of the Spirit) can be _the hope_ of glory.
The application of this can be made very plain. Our whole life in this world looks to some future, however near or bounded it may be; and every power we perfect, every capacity we acquire, every disposition and spirit we foster, is an earnest of something in that future. Here is a man who gives himself to the mastery of a trade. He acquires all its skill, all its methods, all its resources. There is nothing any tradesman can do that he cannot do as well or better. What is that the earnest of? What does it ensure, and as it were put into his hand by anticipation? It is the earnest of constant employment, of good wages, of respect from fellow-workmen, perhaps of wealth. Here, again, is a man with the scientific spirit. He is keenly inquisitive about the facts and laws of the world in which we live. Everything is interesting to him--astronomy, physics, chemistry, biology, history. What is this the earnest of? It is the earnest, probably, of scientific achievements of some kind, of intellectual toils and intellectual victories. This man will enter into the inheritance of science; he will walk through the kingdoms of knowledge in the length of them and the breadth of them, and will claim them as his own. And so it is wherever we choose to take our illustrations. Every spirit that dwells in us, and is cultivated and cherished by us, is an _earnest_, because it fits and furnishes us for some particular thing. _God's_ Spirit also is an earnest of an inheritance which is incorruptible, undefiled, imperishable: can we assure ourselves that we have anything in our souls which promises, because it matches with, an inheritance like this? When we come to die, this will be a serious question. The faculties of accumulation, of mechanical skill, of scientific research, of trade on a great or a small scale, of agreeable social intercourse, of comfortable domestic life, may have been brought to perfection in us; but can we console ourselves with the thought that _these_ have the earnest of immortality? Do they qualify us for, and by qualifying assure us of, the incorruptible kingdom? Or do we not see at once that a totally different equipment is needed to make men at home there, and that nothing can be the earnest of an eternal life of blessedness with God except that Holy Spirit with which He seals His own, and through which He makes them, even here, partakers of the divine nature?