May my heart be blameless in Your statutes, So that I will not be ashamed. Kaph.
NASB95
May my heart be blameless in your statutes, that I may not be put to shame!
ESV
Let my heart be sound in thy statutes; that I be not ashamed.
KJV

The perverseness of the proud will be sure to put them to shame. As the preservative from this shame, David prays therefore for a sound heart—filled with solid principle—delivered into the mold of the word—like the sacrifices of the law—entire for God. Often had he prayed for Divine teaching—now he begs for soundness in the Lord's statutes. How many "have made shipwreck of faith and of a good conscience," from an unsound heart! Ignorant of the spirituality of God's requirements, and resting in an outward obedience, they falsely conceive themselves to be "alive without the law," and "touching the righteousness that is of the law, blameless." Others go a little beyond the surface; while the want of "simplicity and godly sincerity," of brokenness of heart, love to the Savior, and dependence upon His grace, sooner or later discovers to their eternal confusion, that "the root of the matter is" not "in them." "Their root shall be as rottenness, and their blossom shall go up as dust. Their goodness is as a morning cloud, and as the early dew it goes away." An unsound professor, like beautiful fruit, may attract the careless eye; but a more narrow inspection will show a worm at the core, which has spoiled nearly to the surface. Such religion is only a shriveled mass of inactive formality—a dead image of a living thing.

Alas! how common is it to profess to take Christ for a Savior, while the heart is evidently worshiping Mammon as its God!—constrained—not inclined—to the Lord's statutes! How possible is it to be "carnally-minded" in the daily routine of spiritual exercises! How important is the recollection, that no change of place, of company, or of circumstances, can of itself effect a change of heart! "Saul among the prophets" was Saul still; with "another heart" indeed, but not a new heart. Sin was restrained, but not crucified. He "went out," therefore, as one of his progenitors, "from the presence of the Lord," and perished, a miserable apostate from the statutes of his God. Will profession—knowledge—gifts— feelings—privileges—avail for a sound heart? Need we speak of Judas—a follower—no, even, an apostle of Jesus Christ—living in a familiar communion with his Lord—yet with all his privileges—all his profession, "gone to his own place"—the melancholy victim of his own self-deceitfulness? Need we allude to Balaam, "the man whose eyes were open—which heard the words of God—which saw the vision of the Almighty"—who could in the ken of his eye mark the goodness of the Lord's inheritance, and even in the distant horizon catch a glimpse of "Jacob's star and scepter," and yet "loved the wages of unrighteousness?" Need we bring to the mind's eye Ananias and Sapphira? Alexander—and others of like stamp—all of whom once shone as stars in the skies of the church—need we speak of the end of these men, to give energy to the prayer—Let my heart be sound in Your statutes?

How fearful the thought of being "a branch in the true vine" only by profession! to be "taken away" at length, "cast forth as a branch—withered—gathered—cast into the fire—burned!" It is in the inner man that hypocrisy sets up its throne; whence it commands the outward acts into whatever shape or form may be best suited to effect its purpose. The upright Christian will therefore begin with calling in the help and light of God to ascertain the soundness of his heart. "Search me, O God, and know my heart; try me, and know my thoughts; and see if there be any wicked way in me." Can there be a true and solid work, where there is a professed change of heart, and no manifested change of temper and conduct? Can that heart, which is found upon inquiry to be earthly—unprofitable under the power of the word, "regarding" secret "iniquity"—seeking bye-ends of praise, reputation, or gain—and for the attainment of these ends shrinking from the appointed cross—can that heart be sound in the Lord's statutes? Impossible.

But, on the other hand, do you find that your trust in God is sincere, your desire towards Him supreme, your obedience to Him entire? Prize those evidences of soundness of heart. Thank God for them. They are the workings of His mighty Spirit in your heart—perhaps the answer to the prayer which that same Spirit had indited, Let my heart be sound in Your statutes. Diligently improve all the means of grace for keeping your heart in a vigorous state. Be daily—yes, continually—abiding in the vine, and receiving life and health from its fullness. Be much conversant with the word of God—loving it for itself—its holiness—its practical influences. Be chiefly afraid of inward decays—of a barren, sapless notion of experimental truth; remembering, that except your profession be constantly watered at the root, "the things that remain in you will be ready to die." Specially "commune with your own heart." Watch it jealously, because of its proneness to live upon itself—its own graces or fancied goodness (a sure symptom of unsoundness)—instead of "living by the faith of the Son of God." Examine your settled judgment, your deliberate choice, your outgoing affections, your habitual, allowed practice; applying to every detection of unsoundness the blood of Christ, as the sovereign remedy for the diseases of a "deceitful and desperately wicked heart."

But it may be said—will not these exercises of godly jealousy hinder our Christian assurance? Far from it. They will form an efficient preservative from carnal security. They will induce increasing tenderness, activity, and circumspection, in our daily walk; and thus, instead of retarding the enjoyment of our heavenly privilege, they will settle the foundation of a peaceful temperament. It is a light and careless frame, that is the real hindrance to confidence. An unsound professor knows nothing of the true spirit of adoption—nothing of that holy familiarity, with which a child of God unbosoms himself to his heavenly Father; and if he preserves an empty name in the church, he will be put to shame before the universe of God. But the sound heart is connected with "a hope that makes not ashamed"—the full blessing of scriptural confidence. For the heart is made sound by the "sprinkling of the blood of Christ;" and when thus "sprinkled from an evil conscience," we "have boldness" to "draw near"—yes, even to "enter into the holiest," "in full assurance of faith." Blessed privilege of access and communion with our reconciled God! Every moment endears the Savior to our souls, and enlivens the hope of his glorious coming, as the joyful consummation of all the prospects of faith, "Herein is our love made perfect, that we may have boldness in the day of judgment."

This is even more important than to be held in esteem by good men. This is the root of the matter. If the heart be sound in obedience to God, all is well, or will be well. If right at heart we are right in the main. If we be not sound before God, our name for piety is an empty sound. Mere profession will fail, and undeserved esteem will disappear like a bubble when it bursts; only sincerity and truth will endure in the evil day. He who is right at heart has no reason for shame, and he never shall have any. Hypocrites ought to be ashamed now, and they shall one day be put to shame without end: their hearts are rotten, and their names shall rot. This eightieth verse is a variation of the prayer of the seventy-third verse; there the Psalmist sought sound understanding, here he goes deeper, and begs for a sound heart. Those who have learned their own frailty by sad experience, are led to dive beneath the surface, and cry to the Lord for truth in the inward parts. In closing the consideration of these eight verses, let us join with the writer in the prayer, "Let my heart be sound in your statutes."

Exposition of Verses 81 to 88

MY soul faints for your salvation: but I hope in your word.

Mine eyes fail for your word, saying, When will you comfort me?

For I am become like a bottle in the smoke; yet do I not forget your statutes.

How many are the days of your servant? when will you execute judgment on them that persecute me?

The proud have dug pits for me, which are not after your law.

All your commandments are faithful: they persecute me wrongfully; help me.

They had almost consumed me upon earth; but I forsook not your precepts.

Quicken me after your loving-kindness; so shall I keep the testimony of your mouth.

This portion of the gigantic psalm sees the Psalmist in extremis. His enemies have brought him to the lowest condition of anguish and depression; yet he is faithful to the law, and trustful in his God. This octave is the midnight of the psalm, and very dark and black it is. Stars, however, shine out, and the last verse gives promise of the dawn. The strain will after this become more cheerful; but meanwhile it should minister comfort to us to see so eminent a servant of God so hardly used by the ungodly. Evidently in our own persecutions, no strange thing has happened unto us.