The way of attaining to godliness is so far from being known without learning out of the Holy Scriptures that, when it is here plainly revealed, we cannot learn it so easily as the duties of the law, which was known in part by the light of nature, and therefore the more easily assented to. It is the way by which the dead are brought to live to God; and therefore doubtless it is far above all the thoughts and conjectures of human wisdom. It is the way of salvation, in which God will ‘destroy the wisdom of the wise and bring to nothing the understanding of the prudent,’ by discovering things by His Spirit, that ‘the natural man does not receive, for they are foolishness to him, neither can he know them, because they are spiritually discerned’ (1Cor. 1:19, 21; 2:14). ‘Without controversy great is the mystery of godliness’ (1 Tim. 3:16). The learning of it requires double work; because we must unlearn many of our former deeply- rooted notions and become fools, that we may be wise. We must pray earnestly to the Lord to teach us, as well as search the Scriptures, that we may get this knowledge. ‘O that my ways were directed to keep Your statutes!’ ‘Teach me, O Lord, the way of Your statutes; and I will keep it to the end’ (Ps. 119: 5, 33). ‘Teach me to do Your will’ (Ps. 143:10). ‘The Lord direct your hearts to the love of God’ (2Thess. 3:5). Surely these saints did not so much want teaching and directions concerning the duties of the law to be done, as concerning the way and means by which they might do them.
Walter Marshall, The Gospel Mystery of Sanctification (Kindle Edition)