Proverbs 4:23

“Keep thy heart with all diligence, etc.] The mind from vanity, the understanding from error, the will from perverseness, the conscience clear of guilt, the affections from being inordinate and set on evil objects, the thoughts from being employed on bad subjects; and the whole from falling into the hands of the enemy, or being the possession of Satan: great diligence had need be used in keeping it, since it is naturally so deceitful and treacherous; a strict eye is to be kept upon it; all the avenues to it to be watched, that nothing hurtful enters, or evil comes out; it is to be kept by all manner of means that can be thought of, by prayer, hearing, reading, meditation; and, above all, by…”

“with all diligence--or, "above," or "more than all," custody (compare Margin), all that is kept (compare Eze 38:7), because the heart is the depository of all wisdom and the source of whatever affects life and character (Mat 12:35; Mat 15:19).”

“Better, as in the margin, i. e., with more vigilance than men use over anything else. The words that follow carry on the same similitude. The fountains and wells of the East were watched over with special care. The heart is such a fountain, out of it flow the “issues” of life. Shall men let those streams be tainted at the fountain-head? return to 'Top of Page'”

“Heart - Thy thoughts, will, and affections. For - From thence proceed all the actions, as of the natural, so of the spiritual life, which lead to eternal life. Proverbs 4:24”

“4:23 In the Old Testament, the heart represents the center of emotions, thinking, and reasoning (e.g., Gen 6:5; Deut 4:29; Ps 131:1). The heart is crucial in the battle between wisdom and foolishness, between righteousness and evil (see Matt 5:8; 13:15; John 12:40; Rom 6:17).”

“Keep: Pro 22:5, Pro 23:19, Pro 28:26; Deu 4:9; Psa 139:23, Psa 139:24; Jer 17:9; Mar 14:38; Heb 12:15 with all diligence: Heb. above all keeping, Pro 4:7, Pro 3:21, Pro 11:16, Pro 13:3; Ecc 5:13 for: Mat 12:35, Mat 15:19; Mar 7:21-23; Jam 1:14, Jam 1:15 Proverbs 4:24”

“After this general preface the exhortation now becomes special: 23 Above all other things that are to be guarded, keep thy heart, For out from it life has its issues. 24 Put away from thee perverseness of mouth, And waywardness of lips put far from thee. 25 Thine eyes should look straight forward, And thine eyelids look straight to the end before thee. 26 Make even the path of thy feet, And let all thy ways be correct. 27 Turn not aside to the right and to the left; Remove thy foot from evil. Although משׁמר in itself and in this connection may mean the object to be watchfully avoided (cavendi) (vid., under Pro 2:20): thus the usage of the language lying before us applies it, yet only as…”