"Beloved, believe not every spirit, but try the spirits whether they are of God; because many false prophets are gone out into the world."
1 John 4:1
In the apostolic age, there was the greatest outpouring of the Spirit of God that ever was; both as to his extraordinary influences and gifts, and his ordinary operations, in convincing, converting, enlightening, and sanctifying the souls of men. But as the influences of the true Spirit abounded, so counterfeits did also abound: the devil was abundant in mimicking, both the ordinary and extraordinary influences of the Spirit of God, as is manifest by innumerable passages of the apostles' writings. This made it very necessary that the church of Christ should be furnished with some certain rules, distinguishing and clear marks, by which she might proceed safely in judging of the true from the false without danger of being imposed upon. The giving of such rules is the plain design of this chapter, where we have this matter more expressly and fully treated of than any where else in the Bible. The apostle, of set purpose, undertakes to supply the church of God with such marks of the true Spirit as may be plain and safe, and well accommodated to use and practice; and that the subject might be clearly and sufficiently handled, he insists upon it throughout the chapter, which makes it wonderful that what is here said is no more taken notice of in this extraordinary day, when there is such an uncommon and extensive operation on the minds of people, such a variety of opinions concerning it, and so much talk about the work of the Spirit.
The apostle's discourse on this subject is introduced by an occasional mention of the indwelling of the Spirit, as the sure evidence of an interest in Christ. "And he that keepeth his commandments dwelleth in him, and he in him; and hereby we know that he abideth in us, by the Spirit which he hath given us." Whence we may infer, that the design of the apostle is not only to give marks whereby to distinguish the true Spirit from the false, in his extraordinary gifts of prophecy and miracles, but also in his ordinary influences on the minds of his people, in order to their union to Christ, and being built up in him; which is also manifest from the marks themselves that are given, which we shall hereafter notice.