I have found A.W. Pink's writings to be heart-searching and practical as well as doctrinal. I would think that anyone who has actually read a good amount of his writings would not deny this but rather affirm it. Here is a very brief sample.
Keeping the Heart
By A.W. Pink
In Christendom today there are thousands of professing Christians against whom little or nothing in the way of fault could be found so far as their outward lives are concerned. They live moral, clean, upright, honest lives while at the same time the state of their hearts is totally neglected. It is not sufficient to bring our outward deportment into harmony with the revealed will of God. He holds us accountable for what goes on inside, and requires us to keep check on the springs of our actions, the motives which inspire and the principles which regulate us. God requires "truth in the inward parts" (Ps. 51:6). Christ has enjoined us to "take heed" to ourselves "lest at any time our hearts be overcharged with surfeiting and drunkeness, and cares of this life" (Luke 21:34). If I do not look within how then shall I be able to ascertain whether I possess that poverty of spirit, mourning for unholiness, meekness, hungering and thirsting after righteousness and purity of heart upon which the Saviour pronounces His benediction (Matthew 5:1-8)? We must remember that salvation itself is both subjective and objective, for it consists not only of what Christ did FOR His people, but also what He by the Holy Spirit did in them. I have no evidence whatever of my justification apart from my regeneration and sanctification. The one who can say "I am crucified with Christ" judicially can also add "Christ liveth in me" (experimentally), and living by faith in Him is proof that "He loved me and gave himself for me" (Gal. 2:20).
The heart is the center of man's moral nature, of the personality; it equals the whole inner man, it is the fount out of which everything else comes, and is the seat of his thoughts and of his affections and of his will (Gen. 6:5). To guard the heart means that we should live to the glory of God in every respect; that that should be the supreme desire of our life, that we desire to know Him, love Him and serve Him.
If we are to be approved of God it is by no means sufficient that "we make clean the outside of the cup and platter", yet many suppose that that is all that matters. "Cleanse first that which is within" (Matthew 23:26) is our Lord's command. This is rarely given any attention these days, or none at all. It is the devil who seeks to persuade people that they are not responsible for the state of their hearts, that it is impossible for them to change them. Such is most agreeable unto those who think to be "called to heaven on flowery beds of ease." But no regenerate soul, with God's Word before him, will credit such falsehood. The Divine command is plain: "Keep thy heart with all diligence; for out of it are the issues of life" (Prov. 4:23). This is the principal task set before us, for it is at the heart God ever looks, and there can be no pleasing Him while it is unattended to; yea, woe be unto those who disregard it. He who makes no honest endeavor to cast out sinful thoughts and evil imaginations, and who does not mourn over their presence, is a moral leper. He who makes no conscience of the workings of unbelief, the cooling of his affections, the surgings of pride, is a stranger to any work of grace in his soul.
Not only does God bid thee to "keep thy heart," but He requires that you do it "with all diligence;" that is, that you make it your main concern and constant care. The Hebrew word of "keep" signifies to "guard," to watch over this heart (that is, the soul or inward man) as a precious treasure of which thieves are ever ready to rob thee. The devotions of your lips and the labors of your hands are unacceptable to the Lord if your heart is not right in His sight. What husband would appreciate the domestic attentions of his wife if he had good reasons to believe that her affections were alienated from him?
God takes note not only of the matter of our actions but the springs from which they are done and the design of the same. If we become slack and careless in any of these respects, it shows that our love is cooled and that we have become weary of God. The Lord God is He that "ponders the heart" (Prov. 24:12) observing all its motions. He knows whether your alms-deeds are done in order to be seen of men and admired by them, or whether they issue from disinterested benevolence. He knows whether your expressions of good will and love to your brethren are feigned or genuine!
The Bible lays open, as no other book, the turpitude (shameful depravity) and horrid nature of sin as "that abominable thing" which God "hates" (Jer. 4:4), and which we are to detest and shun. It never gives the least indulgence or disposition to sin, nor do any of its teachings lead to licentiousness. It sternly condemns sin in all its forms, and makes known the awful curse and wrath of God which are its due. It not only reproves sin in the outward lives of men, but discovers the secret faults of the heart which is its chief seat. It warns against the first motions, and legislates for the regulating of our spirits, requiring us to keep clean the fountain from which are "the issues of life." Its promises are made unto holiness, and its blessings bestowed upon "the pure in heart." The ineffable (that which cannot be expressed) and exalted holiness of the Bible is its chief and peculiar excellence, as it is also the principal reason why it is disliked by the majority of the unregenerate. The Bible forbids all impure desires and unjust thoughts as well as deeds. It prohibits envy (Prov. 23:17), and all forms of selfishness (Rom. 15:1). It requires us to "cleanse ourselves from all filthiness of the flesh and spirit, and to perfect holiness in the fear of God" (2 Cor. 7:1), and bids us to "abstain from all appearance of evil" (1 Thess. 5:22). Heavenly doctrine is to be matched with heavenly character and conduct. Its requirements penetrate into the innermost recesses of the soul, exposing and censuring all the corruptions found there. The law of man goes no farther than "Thou shall not steal," but that of God "Thou shalt not covet." The law of man prohibits the act of adultery, but the law of God reprehends (finds fault with, censures, blames) the looking upon a woman "to lust after her" (Matthew 5:28). The law of man says, "Thou shalt not murder," that of God forbids all ill-will, malice or hatred (1 John 3:15). It strikes directly at that which fallen nature most cherishes and craves. "Woe unto you when all men shall speak well of you" (Luke 6:26). It prohibits the spirit of revenge enjoins the forgiveness of injuries. and, contrary to the self-righteousness of our hearts, inculcates humility.
Such a task calls for Divine aid, hence help and grace need to be earnestly and definitely sought of the Holy spirit each day. And as, so many today are just playing with the solemn realities of God, never embracing and making them their own. How about you, reader? Is this true of you? Selah.