20 Heb “[it] restores life.” Elsewhere the Hiphil of שׁוּב (shuv, “return”) when used with נֶפֶשׁ (nefesh, “life”) as object, means to “rescue or preserve one’s life” (Job 33:30; Ps 35:17) or to “revive one’s strength” (emotionally or physically; cf. Ruth 4:15; Lam 1:11, 16, 19). Here the point seems to be that the law preserves the life of the one who studies it by making known God’s will. Those who know God’s will know how to please him and can avoid offending him. See v. 11a.
21 Traditionally, “the testimony of the Lord.” The noun עֵדוּת (’edut) refers here to the demands of God’s covenant law.
22 God’s covenant contains a clear, reliable witness to his moral character and demands.
23 Or “the [morally] naive,” that is, the one who is young and still in the process of learning right from wrong and distinguishing wisdom from folly.
24 Or “just.” Perhaps the idea is that they impart a knowledge of what is just and right.
25 Heb “[they] make happy [the] heart.” Perhaps the point is that they bring a sense of joyful satisfaction to the one who knows and keeps them, for those who obey God’s law are richly rewarded. See v. 11b.
26 Heb “command.” The singular here refers to the law as a whole.
27 Because they reflect God’s character, his commands provide a code of moral and ethical purity.
28 Heb [they] enlighten [the] eyes.
29 Heb “the fear of the Lord is clean.” The phrase “fear of the Lord” probably refers here to the law, which teaches one how to demonstrate proper reverence for the Lord. See Ps 111:10 for another possible use of the phrase in this sense.
30 Heb “[it] stands permanently.”
31 Trustworthy and absolutely just. The Lord’s commands accurately reflect God’s moral will for his people and are an expression of his just character.

In other versions

ESVEnglish Standard Version

The law of the Lord is perfect,

reviving the soul;

the testimony of the Lord is sure,

making wise the simple;

the precepts of the Lord are right,

rejoicing the heart;

the commandment of the Lord is pure,

enlightening the eyes;

the fear of the Lord is clean,

enduring forever;

the rules of the Lord are true,

and righteous altogether.

NIVNew International Version (2011)

The law of the Lord is perfect,

refreshing the soul.

The statutes of the Lord are trustworthy,

making wise the simple.

The precepts of the Lord are right,

giving joy to the heart.

The commands of the Lord are radiant,

giving light to the eyes.

The fear of the Lord is pure,

enduring forever.

The decrees of the Lord are firm,

and all of them are righteous.

CSBChristian Standard Bible

The instruction of the Lord is perfect,

renewing one’s life;

the testimony of the Lord is trustworthy,

making the inexperienced wise.

The precepts of the Lord are right,

making the heart glad;

the command of the Lord is radiant,

making the eyes light up.

The fear of the Lord is pure,

enduring forever;

the ordinances of the Lord are reliable

and altogether righteous.

NLTNew Living Translation

The instructions of the Lord are perfect,

reviving the soul.

The decrees of the Lord are trustworthy,

making wise the simple.

The commandments of the Lord are right,

bringing joy to the heart.

The commands of the Lord are clear,

giving insight for living.

Reverence for the Lord is pure,

lasting forever.

The laws of the Lord are true;

each one is fair.

LEBThe Lexham English Bible

The law of Yahweh is perfect, reviving life.

The testimony of Yahweh is firm, making wise the simple.

The precepts of Yahweh are right, making the heart rejoice.

The command of Yahweh is pure, enlightening the eyes.

The fear of Yahweh is pure, enduring forever.

The ordinances of Yahweh are true; they are righteous altogether,

KJV 1900King James Version

The law of the Lord is perfect, converting the soul:

The testimony of the Lord is sure, making wise the simple.

The statutes of the Lord are right, rejoicing the heart:

The commandment of the Lord is pure, enlightening the eyes.

The fear of the Lord is clean, enduring for ever:

The judgments of the Lord are true and righteous altogether.

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