"...There are very many also who form such an idea of the divine mercy as yields them very little comfort. For they are harassed by miserable anxiety while they doubt whether God will be merciful to them. They think, indeed, that they are most fully persuaded of the divine mercy, but they confine it within too narrow limits. The idea they entertain is, that this mercy is great and abundant, is shed upon many, is offered and ready to be bestowed upon all; but that it is uncertain whether it will reach to them individually, or rather whether they can reach to it. Thus their knowledge stopping short leaves them only mid-way; not so much confirming and tranquilizing the mind as harassing it with doubt and disquietude.
"Very different is that feeling of full assurance (πλεροφορία) which the Scriptures uniformly attribute to faith—an assurance which leaves no doubt that the goodness of God is clearly offered to us. This assurance we cannot have without truly perceiving its sweetness, and experiencing it in ourselves. Hence from faith the Apostle deduces confidence, and from confidence boldness. His words are, “In whom (Christ) we have boldness and access with confidence by the faith of him,” (
Eph. 3:12) thus undoubtedly showing that our faith is not true unless it enables us to appear calmly in the presence of God. Such boldness springs only from confidence in the divine favor and salvation. So true is this, that the term faith is often used as equivalent to confidence.
16. The principal hinge on which faith turns is this: We must not suppose that any promises of mercy which the Lord offers are only true out of us, and not at all in us: we should rather make them ours by inwardly embracing them. In this way only is engendered that confidence which he elsewhere terms peace (
Rom. 5:1); though perhaps he rather means to make peace follow from it. This is the security which quiets and calms the conscience in the view of the judgment of God, and without which it is necessarily vexed and almost torn with tumultuous dread, unless when it happens to slumber for a moment, forgetful both of God and of itself. And verily it is but for a moment. It never long enjoys that miserable obliviousness, for the memory of the divine judgment, ever and anon recurring, stings it to the quick.
"In one word, he only is a true believer who, firmly persuaded that God is reconciled, and is a kind Father to him, hopes everything from his kindness, who, trusting to the promises of the divine favor, with undoubting confidence anticipates salvation; as the Apostle shows in these words, “We are made partakers of Christ, if we hold the beginning of our confidence steadfast unto the end,” (
Heb. 3:14). He thus holds, that none hope well in the Lord save those who confidently glory in being the heirs of the heavenly kingdom."
http://www.ccel.org/ccel/calvin/institutes.v.iii.html (emphasis added)
