Understanding Psalm 37: The mouth of the righteous person reflects on wisdom. His tongue speaks what is fair. Psalm 37:30

Psalm 37 is a hymn that belongs to the genre of the sapiential songs in the Bible. Psalm 37 is not a psalm of thanksgiving or a plea to God for help. Psalm 37 is an educational Psalm that seeks to explain that there are two paths and two rewards. This psalm or hymn is in essence a continuation of Psalm 1, the Psalm of the Two Ways.
This Psalm emphasizes, among other things, the importance of wisdom for living, and how this wisdom, lived righteously, blesses men. But also, Psalm 37 addresses the ethical problem of the two paths in a very particular way. It could be said that this song is deeply connected to the story of Job in the Bible. Job in the Bible began to suffer a series of misfortunes, and he began to wonder why his enemies prospered while he was left with nothing. In this sense, this song raises the question of why the wicked and sinners can prosper, and this is something that can confuse many sensible men. The Psalm answers that the prosperity of the wicked is always ephemeral, while in the long run, sensible men, who may suffer adversity, always find it momentary and not lasting.
This is why the Psalm begins by teaching that the sensible men should put their trust in God: "Trust the LORD, and do good things. Live in the land, and practice being faithful. Be happy with the LORD, and he will give you the desires of your heart" Psalm 37:3-4. Security or trust in God has a very deep spiritual meaning in the Bible, because security is not simply faith; security is related to the knowledge of the ethical laws of the universe, like the law of sowing and reaping.
And Psalm 37, after discussing the fate of the wicked, expresses that wise men can walk securely and that their relationship with the divine sustains them, with these words: "The mouth of the righteous person reflects on wisdom. His tongue speaks what is fair. The teachings of his God are in his heart. His feet do not slip" Psalm 37:30-31.
Understanding Psalm 37 means understanding the importance of being edifying, progressive, and benevolent like God, and that this is in harmony with divine laws. This is where security in God lies, and although in certain situations, like Job, everything seems to go against the sensible men, in the long run, the wicked are punished and the wise are rewarded.

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