1 Psa 37:1-40. A composed and uniform trust in God and a constant course of integrity are urged in view of the blessedness of the truly pious, contrasted in various aspects with the final ruin of the wicked. Thus the wisdom and justice of God's providence are vindicated, and its seeming inequalities, which excite the cavils of the wicked and the distrust of the pious, are explained. David's personal history abundantly illustrates the Psalm.
The general sentiment of the whole Psalm is expressed. The righteous need not be vexed by the prosperity of the wicked; for it is transient, and their destiny undesirable.

3 Trust - sure of safety.
shalt thou dwell - or, "dwell thou"; repose quietly.
verily ... fed - or, "feed on truth," God's promise (Psa 36:5; compare Hos 12:1).

4 desires - (Psa 20:5; Psa 21:2), what is lawful and right, really good (Psa 84:11).

5 Commit thy way - (Pro 16:3). Works - what you have to do and cannot set forth as a burden.
trust ... in him - literally, "on Him." He will do what you cannot (compare Psa 22:8; Psa 31:6). He will not suffer your character to remain under suspicion.

7 Rest in - literally, "Be silent to the Lord."
and wait - Be submissive - avoid petulance and murmurings, anger and rash doing.

9 Two reasons: The prosperity of the wicked is short; and the pious, by humble trust, will secure all covenant blessing, denoted here by "inherit the earth" (compare Psa 25:13).

10 shall not be - literally, "is not" - is not to be found.

11 peace - includes prosperity.

12 gnasheth ... teeth - in beastly rage.

13 (Compare Psa 2:4).
seeth - knows certainly.
his day - of punishment, long delayed, shall yet come (Heb 10:37).

14 sword, and ... bow - for any instruments of violence.
slay - literally, "slaughter" (1Sa 25:11).
poor and needy - God's people (Psa 10:17; Psa 12:5). The punishment of the wicked as drawn on themselves - often mentioned (compare Psa 7:15, Psa 7:16; Psa 35:8).

16 riches - literally, "noise and tumult," as incidental to much wealth (compare Psa 39:6). Thus the contrast with the "little" of one man is more vivid.

17 Even the members of the body needed to hold weapons are destroyed.

18 God, who knows His people's changes, provides against evil and supplies all their need.

20 While the wicked, however mighty, are destroyed, and that utterly, as smoke which vanishes and leaves no trace.

21 payeth not - not able; having grown poor (compare Deu 15:7). Ability of the one and inability of the other do not exclude moral dispositions. God's blessing or cursing makes the difference.

22 cut off - opposed to "inherit the earth" (compare Lev 7:20, Lev 7:21).

23 steps - way, or, "course of life"; as ordered by God, failures will not be permanent.

26 his seed is blessed - literally, "for a blessing" (Gen 12:2; Psa 21:6). This position is still true as the rule of God's economy (1Ti 4:8; 1Ti 6:6).

27 The exhortation is sustained by the assurance of God's essential rectitude in that providential government which provides perpetual blessings for the good, and perpetual misery for the wicked.

30 The righteous described as to the elements of character, thought, word, and action.

31 steps - or, "goings" - for conduct which is unwavering (Psa 18:36).

32 The devices of the wicked against the good fail because God acquits them.

34 On the contrary, the good are not only blessed, but made to see the ruin of their foes.

35 of which a picture is given, under the figure of a flourishing tree (compare Margin), which soon withers.

36 he was not - (Compare Psa 37:10).

37 By "the end" is meant reward (Pro 23:18; Pro 24:14), or expectation of success, as in Psa 37:38, which describes the end of the wicked in contrast, and that is cut off (compare Psa 73:17).

38 together - at once; entirely (Psa 4:8).

39 strength - (Psa 27:1; Psa 28:8).
trouble - straits (Psa 9:9; Psa 10:1). In trust and quietness is the salvation of the pious from all foes and all their devices.