What does the Bible say about discernment?

But then we must understand what it is, this judgment which the Lord forbids. And here two things should be clear to us: first, that we are to judge of things, ― of the evil and the good in either principles or acts presented to us. Here we have what touches ourselves: it is necessary that we should have our "senses exercised to discern both good and evil" (Heb. 5:14). It is true that we are to be "wise concerning that which is good and simple concerning evil" (Rom. 16:19); and this word "simple" (literally, pure, unmixed"*) is a warning as to the defiling nature of evil, which if realized will forbid unnecessary occupation with it, as the contrast with "wise" would lead us to understand. Yet we must know it so far as to know it to be evil, or we have no safeguard against it. Judgment, therefore, as to whatever lies in our path, is absolutely necessary for us; and the character of the world and the state of Christians both warn us to be watchful.

To seek counsel as to whether a thing be evil, and still to seek counsel when we know it is evil, are two acts altogether distinct. Not only may we ask of the Lord to give us discernment as to evil, but more, this is without contradiction a duty it behoves us sedulously and with honesty to fulfil. Scripture tells us that this discernment is a distinctive characteristic of "those who are of full age." (Heb. 5:14.)

He prays for discernment (judgment). Sometimes this may signify a “spiritual sense of smell,” or “taste;” but here it has the sense of taste for judgment, discernment, reason. Paul prays for the Philippians in chapter one verse 10: “That ye may approve things that are excellent,” or as the N.I.V. puts it: “ … so that you may be able to discern what is best … ” For the believer it is not a question of refusing sin or sinful things, but of discerning what is profitable and constructive, and what is not. Good judgment and knowledge are essential for spiritual growth. “ … but solid food belongs to full-grown men, who, on account of habit, have their senses exercised for distinguishing both good and evil” (Heb. 5:14). Now this kind of spiritual discernment does not come to us automatically, as we learn from the verse in Hebrews 5. It comes with practise. That is why the writer begins this verse 66 with: “Teach me … ” Are we willing to be taught?

Is it necessary that we should be informed of all the history of evils or of all the details of the workings of evil in order to be preserved from it? This word answers decisively. To have our souls filled with the good Word of God is our serious need — not occupied with discerning evil, but so occupied with good that any evil that may present itself may immediately be discerned and judged. “Wise unto that which is good” is a blessed word for our souls. Just as a bank teller is trained diligently in handling only good currency, in order that a spurious coin or bill would be immediately detected, so should our souls be well-trained in that which is good. Then the evil, whatever form it takes, would be discerned through its dissimilarity to the good.

We may indeed be thankful that God over-ruled the uprising of these early heresies to the giving us of these simple tests, which are still as valid as in the day they were first propounded. Hereby indeed we may know the spirit of truth and the spirit of error. If we are wise, when confronted with doubtful teachings, we will at once apply these tests instead of leaning to our own understanding.

In contradistinction to these men who were of the world, and who spoke as of the world, the apostles were of God, and to them was committed the testimony of God, and whosoever was of God heard them. In this way we distinguish between the spirit of truth and the spirit of error. Nothing can be much more simple. Christ is the touchstone for everything. He is the true light in which everything is seen as it really is, and we have in addition to this, the writings of the apostles of our Lord, and we must reject everything that is not in agreement with their words.

Here however is special need of discernment; and the truth is essential that we be not misled. Accordingly the guard is furnished in 1 John 4:1-6. The first test against error is Jesus Christ come in flesh whom the Holy Spirit always glorifies; whereas the spirit that confesses Him not is not of God. The second is not the law and the prophets (divinely inspired as they were), but the new testimony of Christ by apostles and prophets. He that knows God hears us; he that is not of God does not hear us. The New Testament also is indispensable to guard against the spirit of error.

But there are many false prophets who have gone out into the world claiming to be speaking by the Holy Spirit. In every age since the apostolic times, various systems of teachings have been urged upon the people of God. They are usually antichristian in character. They are usually commended as a perfecting of, or progress beyond, the Christian revelation. Their propagators claim to be taught by the Spirit of God. It becomes necessary therefore to test the teaching we are invited to receive. Our apostle warns against believing every spirit; he exhorts us to try them, to see whether they are of God (ver. 1). He gives us also the infallible tests by which to try the claims or pretensions of all who profess to speak for God.

And what are these tests? He gives us two sure rules by which we may judge whether a teacher or prophet is bringing the truth of God. If John tells us not to believe every spirit, he means that we must not accept as true the profession one may make that he is speaking by the Spirit; and if he says, "Try the spirits whether they are of God," he would have us realize there is an absolutely sure way of detecting false claims, and exposing the pretensions of those who are assuming to be what they are not.

There are two great spiritual agencies at work, viz., the Spirit of Truth and the Spirit of Error. The Apostle John in his Epistle shows that there are two infallible discriminating tests to which every spirit may be subjected. The spirits which are in accord with the Spirit of Truth (a) confess Jesus Christ come in flesh, i.e., the true import of His incarnation: (b) they hear the Apostles, i.e., they listen to the messages conveyed in the Epistles as real messages from God through the Apostles.

The Apostle John bids us try the spirits. The test is, Do they believe that Jesus Christ is come in the flesh? If they fail in this test, they are not of God.