He shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you. – John 14:26

All that the believer truly knows that is profitable to himself is taught him by the Holy Spirit. We may learn very much from the Word of God morally and mentally, but the Christian philosopher understands that there is a distinction between soul and spirit; that the mere natural soul or intellect of man may instruct itself well enough out of the Word of God, but that spiritual things are only to be spiritually discerned, and that until that third, higher principle-the spirit-is infused into us in regeneration, we have not even the capability or the possibility of knowing spiritual things… Now, the Spirit of God first gives us a spirit, and then afterwards educates that spirit; and all that that spirit knows is taught it by the Holy Ghost. Perhaps the first thing that we learn is sin: He reproves us of sin. No man knows the exceeding sinfulness of sin, but by the Holy Ghost. You may punish a man, you may tell him of the wrath of God, and of hell, but you cannot make him know what an evil and a bitter thing sin is till the Holy Ghost hath taught it to him. ‘Tis an awful lesson indeed to learn, and when the Holy Spirit makes us sit down upon the stool of penitence, and begins to drill this great truth into us, that sin is damnation in the bud, that sin is hell in the germ: then when we begin to perceive it, we cry out, “Now I know how vile I am, my soul abhorreth itself in dust and ashes.” No man, I repeat it, will ever know the sinfulness of sin by argument, by punishment, by moral discipline, or by any means apart from the education of the Holy Ghost. It is a truth beyond the reach of human intellect to know how base a thing sin is. The spirit alone, engrafted and given by the Holy Spirit,-that spirit alone can learn the lesson, and only the Holy Ghost can teach it. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/0315.cfm