One aspect of the doctrine of Sola Scriptura that sometimes seems problematic is what the Protestant tradition has called “the internal testimony of the Spirit.” Is this the Protestant version of the Mormon “burning in the bosom?” Is this the catch all excuse-maker justifying all manner of iniquity? I cannot submit to my elders because my conscience just won’t let me. I cannot stay with my wife because the Spirit has not revealed that to be God’s will for my life. I must become Eastern Orthodox because my conscience demands… oh wait a second. Woops.
Well first off, we need to recognize that the Bible does speak to this. There is an internal testimony of the Spirit: “And by this we know that he abides in us, by the Spirit whom he has given us” (1 Jn. 3:24). But John continues: “Beloved do not believe every spirit, but test the spirits to see whether they are from God, for many false prophets have gone out into the world” (1 Jn. 4:1). So just because somebody feels assured of something doesn’t mean it’s the Holy Spirit. False spirits lead people away from God while the Holy Spirit leads people into communion with God. The central test for the spirits comes down to whether they confess that Jesus is from God (1 Jn. 4:2-3). But there is also a fellowship and submission test: Those spirits that are not from God are collaborators with the world: “therefore they speak from the world, and the world listens to them” (1 Jn. 4:5). Those who have the Spirit of God inside of them overcome the world because “he who is in you is greater than he who is in the world” (1 Jn. 4:4). But then John says this: “We are from God. Whoever knows God listens to us; whoever is not from God does not listen to us. By this we know the Spirit of truth and the spirit of error” (1 Jn. 4:6). The internal testimony of the Spirit is not at odds with the apostolic teaching. The internal testimony of the Spirit is not an anti-rational trump card that discerns loop holes, exceptions, and penumbra in the Scriptures. Rather, the internal testimony of the Spirit confirms precisely what the apostles taught. And what did the apostles teach? The New Testament Scriptures, those writings authored and sponsored by the hand-picked witnesses of Jesus.
However, sometimes the internal testimony of the Spirit is presented as R.C. Sproul says in such a way as to give “the impression that the biblical data, apart from the internal testimony, is insufficient to provide a rational-evidential basis for faith in Christ and that the Holy Spirit either provides new internal evidence for the believer that is unavailable to all, or that he gives the Christian the ability to leap over the evidence (being either insufficient or contrary) by an act of faith” (Scripture Alone, 75-76). In other words, the internal testimony of the Spirit is not the Holy Spirit communicating secret information that is not available to everyone, nor is it some kind of irrational leap over the chasm of insufficient evidence. Then what it is? Sproul cites Calvin who says that this doctrine means that the Holy Spirit teaches men inwardly such that they “acquiesce implicitly in Scripture; that Scripture, carrying its own evidence along with it, deigns not to submit to proofs and arguments, but owes the full conviction with which we ought to receive it by the testimony of the Spirit.” Calvin is not saying that people may appeal to their conscience and get the Bible to say whatever they want it to say. He’s not saying that the Bible really is one of those choose-your-own-adventure novels. He’s saying the Holy Spirit compels men to receive what the Bible actually says. As Sproul puts it, “for Calvin, the testimony of the Spirit does not cause men to acquiesce contrary to the evidence but into the evidence of Scripture” (77, emphasis mine).
To summarize, the Bible itself teaches that the Holy Spirit is given so that we might hear the words of the apostles. Those who have the Holy Spirit listen to the apostles. What infallible record has been left by the apostles? Their authoritative writings collected in the pages of the New Testament. The internal testimony of the Spirit compels men to read and listen to the actual words, the actual claims, the actual evidence set forth in the Scriptures themselves and to receive them, believe them, and obey them. The deep irony is that those who deny Sola Scriptura often sound far more mystical (and might we say Mormon?) than this traditional Protestant position. Rather than being driven back to the text of Scripture, to study the text, to wrestle with the text like the faithful Bereans did with Paul’s gospel, many in the Orthodox and Roman traditions dismiss such study as hopelessly ambiguous, individualistic, and at worst dangerously tending toward heresy. What you need, they seem to say, is the spirit of tradition to lead you and guide you. But as John says, you really must test the spirits. Some of them don’t listen to the apostles.