“They who strive to build up firm faith in Scripture through disputation are doing things backwards… Since for unbelieving men religion seems to stand by opinion alone, they, in order not to believe anything foolishly or lightly, both wish and demand rational proof that Moses and the prophets spoke divinely.
But I reply: the testimony of the Spirit is more excellent than all reason. For as God alone is a fit witness of himself in his Word, so also the Word will not find acceptance in men’s hearts before it is sealed by the inward testimony of the Spirit. The same Spirit, therefore, who has spoken through the mouths of the prophets must penetrate into our hearts to persuade us that they faithfully proclaimed what had been divinely commanded.
By this power we are drawn and inflamed, knowingly and willingly, to obey him, yet also more vitally and more effectively than by mere human willing or knowing… I speak of nothing other than what each believer experiences within himself.”
(John Calvin, quoted in Iain Murray, Evangelicalism Divided, 157-158)