I found the conclusion to John Murray’s sermon “Holy Scripture” (based on 2 Tim 3.16-17) to be worth passing along:
I think we have sometimes so reacted against a pietism that smacks of piosity that we have tended to neglect biblical terms and concepts. Let us take note of the dignity and meaning that belongs to the designation ‘man of God’, God’s man. He is the person laid hold upon by God, separated unto God, possessed by God. He is a man who is not his own, not his own servant, not even that of men though he serves men. He is the God-possessed man, the God-dedicated man, the consecrated man, the man who lives for God, who speaks for God, who speaks of God. It is the purpose which Scripture serves for that man of which Paul here speaks. And note the apostle’s universals – ‘complete’,’ thoroughly furnished’, ‘every good work’. It is completeness, thoroughness, and comprehensiveness all along the line. This is nothing less than the great truth of the perfection of Scripture. There is no situation in which we are placed, no demand that arises, for which Scripture as the deposit of the manifold wisdom of God is not adequate and sufficient. It is the Scripture that provides the equipment, the furnishings, the investments, that prepare us for the kingdom of God, ’till we all come in the unity of the faith and of the knowledge of the Son of God unto a perfect man, unto the measure of the stature of the fulness of Christ’ and are ‘filled unto all the fulness of God’.
We miss one of the chief lessons of this text if we do not appreciate the emphasis that all Scripture is directed to the end of fitting the man of God for every good work. If we are thinking of Scripture in its discrete parts, the thought is that ‘every Scripture’ is directed to this end. The apostle makes no distinction. All Scripture in its total extent and discrete parts is pertinent faith and practice. Why? Because all Scripture is God-breathed and no detail of what the mouth of God has spoken is dispensable.
Of course, not all of Scripture is of equal importance. In Scripture there is what is central and what is more peripheral. But it is a perfect man of God that the Scripture is to equip, not a mutilated or maimed man of God, not furnished unto some good works, not partly furnished to every good work, but ‘thoroughly furnished unto every good work’. Only Scripture in its entirety is adequate to that end.
“Holy Scripture” in Collected Writings of John Murray, Vol. 3: Life; Sermons; Reviews pg. 261-62. (Bold emphasis added.)
I love how Murray directs us toward the true purpose of scripture and the true sufficiency of scripture. There are, to be sure, spheres of life that are better served by appeals to wisdom and experience as Scripture may only speak to them tangentially and incidentally. And yet the true purpose of God’s word is to equip the redeemed man (and woman!) of God for every good work. In this task for which Scripture is indeed wholly sufficient and wholly infallible!