Psalm 38 begins a group of four related psalms that closes Book I (i.e., Psalms 38-41). These four psalms are linked by central themes. All are confessions of sin in the midst of troubles—the troubles in at least three of these being serious illness and enemies (while the other, Psalm 40, concerns enemies rising during a time of distress, which could also be related to a time of illness).

As the sicknesses in these psalms are a result of sin on David's part, it is possible that they are all one and the same sickness resulting from the same sin. It could be, as suggested in the Beyond Today Bible Commentary on Psalm 6, that the plague David suffers is the one he prayed to come on him in place of the populace after he sinned in the numbering of Israel (see 2 Samuel 24; 1 Chronicles 21). However, the Bible does not actually say whether or not David was then afflicted. The sicknesses in these psalms could well concern another time. The betrayal in Psalm 41 may hint at the time of national rebellion under Absalom with the assistance of David's friend and counselor Ahithophel (if deep depression contributed to David becoming physically ill at that time, though the Bible does not tell us).

The NIV translation of Psalm 38's superscription refers to the psalm as a "petition." The King James and New King James give the more literal rendering of this verbal phrase (which is also found in the superscription of Psalm 70) as "To bring to remembrance." Though God knows our needs, He nevertheless expects us to remind Him of them in prayer—perhaps to remind ourselves of our need for Him and His help.

David confesses his sin, which he labels foolishness, and asks for relief from God's heavy hand. God chastens him because of His sin (verses 3, 5). Sickness is not always due to a person's sins (see Job 1-2; John 9:1-3). But sometimes it is, as the numerous instances of God sending plague as punishment attests. Proverbs 3:11-12 explains that God's chastening is done out of love—just as a father disciplines his son. The book of Hebrews quotes these verses (Hebrews 12:5-6) and goes on to comment further, explaining how it all works toward a positive outcome (verses Hebrews 12:7-11).

The ordeal leaves David weak from festering sores (verse 5) and inflammation (verse 7). He is depressed by guilt (verse 4) and a lack of peace (verse 8). In verse 10, David speaks of his failing strength and the light having gone out of his eyes. We saw similar expressions in Psalm 6:7 and Psalm 13:3. In its note on 6:7, the Zondervan NIV Study Bible says: "In the vivid language of the O[ld] T[estament] the eyes are dimmed by failing strength (see Psalm 38:10; 1 Samuel 14:27-29...Jeremiah 14:6), by grief (often associated with affliction: Psalm 31:9; Psalm 88:9; Job 17:7; Lamentations 2:11) and by longings unsatisfied or hope deferred (see Psalm 69:3; Psalm 119:82, Psalm 123; Deuteronomy 28:32; Isaiah 38:14)." This idiom has passed over into English. We sometimes speak of the light, spark or sparkle having left someone's eye—meaning the person has no further sense of joy in living.

Friends and family won't come near David in his illness (verse 11). Enemies conspire against him (verse 12). Isolated and absorbed in his suffering, he has no way to know what's going on and no one to talk to—like a deaf and mute person (verses 13-14). His silence may also be part of a conscious effort to avoid saying something rash or foolish to or before others and thereby sinning further, as he says in the next psalm (Psalm 39:1-2).

But David hopes in God to hear and answer His prayer (Psalm 38:15). His silence is only before other people. To God He pours out His heart, confessing his sin and pleading with God to deliver him soon (verses 15-22). Indeed, if the other sickness psalms concern this period, then David had much to say to God as He composed these prayerful hymns.