1 John 4:1

We are obliged from time to time to recur to certain topics in order to affirm truths which are connected with them. We repeat then here, that as the Lord is by the apostle proclaimed as the awarder of both weal and woe, He must be either the Creator, or (as Marcion would be loth to admit) One like the Creator, “with whom it is a righteous thing to recompense tribulation to them who afflict us, and to ourselves, who are afflicted, rest, when the Lord Jesus shall be revealed as coming from heaven with the angels of His might and in flaming fire.” The heretic, however, has erased the flaming fire , no doubt that he might extinguish all traces herein of our own God. But the folly of the obliteration is clearly seen. …

And the apostles, who speak of God, in establishing the truth of the advent of the Lord Jesus Christ, have each of them indicated the appearing of these abominable and ruin-working men, and have openly announced their lawless deeds. First of all Peter, the rock of the faith, whom Christ our God called blessed, the teacher of the Church, the first disciple, he who has the keys of the kingdom, has instructed us to this effect: “Know this first, children, that there shall come in the last days scoffers, walking after their own lusts. And there shall be false teachers among you, who privily shall bring in damnable heresies.” After him, John the theologian, and the beloved of Christ, in harmony with him, cries, “The children of the devil are manifest; and even now are there many antichrists; but go not after them. …

Chapter 34. 39. Petilianus quotes also the warning of the Apostle John, that we should not believe every spirit, but try the spirits whether they are of God, as though this care should be bestowed in order that the wheat should be separated from the chaff in this present world before its time, and not rather for fear that the wheat should be deceived by the chaff; or as though, even if the lying spirit should have said something that was true, it was to be denied, because the spirit whom we should abominate had said it. But if any one thinks this, he is mad enough to contend that Peter ought not to have said, "Thou art the Christ, the Son of the living God," because the devils had already said something to the same effect. …

Since faith, then, is in our power, inasmuch as every one believes when he likes, and, when he believes, believes voluntarily; our next inquiry, which we must conduct with care, is, What faith it is which the apostle commends with so much earnestness? For indiscriminate faith is not good. Accordingly we find this caution: “Brethren, believe not every spirit, but try the spirits whether they are of God.” Nor must the clause in commendation of love, that it “believeth all things,” be so understood as if we should detract from the love of any one, if he refuses to believe at once what he hears. …

11. “Beloved, believe not every spirit.” Because he had said, “In this we know that He abideth in us, by the Spirit which He hath given us.” But how this same Spirit is known, mark this: “Beloved, believe not every spirit, but prove the spirits whether they be from God.” And who is he that proves the spirits? A hard matter has he put to us, my brethren! It is well for us that he should tell us himself how we are to discern them. He is about to tell us: fear not: but first see; mark: see that hereby is expressed the very thing that vain heretics taunt us withal. Mark, see what he says, “Beloved, believe not every spirit, but prove the spirits whether they be from God.” The Holy Spirit is spoken of in the Gospel by the name of water; where the Lord “cried and said, If any man thirst, let him come unto me, and drink. …

38. ‘And it is not fitting to boast at the casting forth of the demons, nor to be uplifted by the healing of diseases: nor is it fitting that he who casts out devils should alone be highly esteemed, while he who casts them not out should be considered nought. But let a man learn the discipline of each one and either imitate, rival, or correct it. For the working of signs is not ours but the Saviour’s work: and so He said to His disciples: “Rejoice not that the demons are subject to you, but that your names are written in the heavens.” For the fact that our names are written in heaven is a proof of our virtuous life, but to cast out demons is a favour of the Saviour who granted it. …

3. And although, again, he conceal his natural falsehood, and pretend to speak truth with his lips; yet are we ‘not ignorant of his devices,’ but are able to answer him in the words spoken by the Spirit against him; ‘But unto the ungodly, said God, why dost thou preach My laws?’ and, ‘Praise is not seemly in the mouth of a sinner.’ For even though he speak the truth, the deceiver is not worthy of credit. And whereas Scripture shewed this, when relating his wicked artifices against Eve in Paradise, so the Lord also reproved him, first in the mount, when He laid open ‘the folds of his breast-plate,’ and shewed who the crafty spirit was, and proved that it was not one of the saints, but Satan that was tempting Him. …

We ought then carefully to notice this threefold order, and with a wise discretion to analyse the thoughts which arise in our hearts, tracking out their origin and cause and author in the first instance, that we may be able to consider how we ought to yield ourselves to them in accordance with the desert of those who suggest them so that we may, as the Lord’s command bids us, become good money-changers, whose highest skill and whose training is to test what is perfectly pure gold and what is commonly termed tested , or what is not sufficiently purified in the fire; and also with unerring skill not to be taken in by a common brass denarius, if by being coloured with bright gold it is made like some coin of great value; and not only shrewdly to recognize coins stamped with the heads of usurpers, but with a still shrewder skill to detect those which have the image of the right king, but are …