Answer
In Psalm 108:1–5, King David praises God for His great love and faithfulness. The words are taken directly from Psalm 57:7–11. Amid great adversity, David declares his total confidence in God’s protection: “My heart is steadfast, O God! I will sing and make melody with all my being!” (Psalm 108:1, ESV).
The word heart speaks of a person’s inward being—one’s mind, will, emotions, and inclinations. A “steadfast” heart is marked by firm determination or resolution. To be steadfast is to be established, permanent, steady, and unshakeable. David’s whole inner self—his soul—was fixed and firmly settled on trusting God.
With a steadfast heart, David would not be shaken by threatening circumstances or blown about by the winds of misfortune. He repeated the refrain twice in Psalm 57:7, emphasizing his concrete resolve to trust in God: “My heart, O God, is steadfast, my heart is steadfast; I will sing and make music.” David wrote Psalm 57 as a heartfelt prayer for deliverance while hiding in a cave and being hunted down by King Saul. Despite the threat to his life, David voiced unswerving confidence in the Lord to rescue him from a desperate situation.
Sin is the greatest threat to a steadfast heart. After David committed adultery with Bathsheba and then murdered her husband, Uriah, David’s heart was tainted by sin. A year later, Nathan confronted him, and David acknowledged the seriousness of his offenses against God (Psalm 51:3–6). He confessed his transgressions and repented. David also accepted that his sin resulted from a compromised and corrupt heart. David prayed, asking God to remove the stain of sin and restore his steadfastness of heart: “Create in me a clean heart, O God, And renew a steadfast spirit within me” (Psalm 51:10, NKJV).
Having a steadfast heart is closely related to faithfulness (1 Thessalonians 1:3; 2 Thessalonians 1:4). The quality of steadfastness belongs to a person who is faithful, reliable, and loyal to the end. Paul encouraged Christians to “be steadfast, immovable, always abounding in the work of the Lord, knowing that in the Lord your labor is not in vain” (1 Corinthians 15:58, ESV; see also 1 Timothy 6:11; 2 Timothy 3:10; Titus 2:2, ESV). Jesus is the most excellent example of someone who is steadfast in heart (2 Thessalonians 3:5; Romans 15:3–5).
James encouraged believers to embrace trials that test our faith because they produce steadfastness in us: “Count it all joy, my brothers, when you meet trials of various kinds, for you know that the testing of your faith produces steadfastness. And let steadfastness have its full effect, that you may be perfect and complete, lacking in nothing” (James 1:2–4, ESV). The apostle Peter affirmed, “And the God of all grace, who called you to his eternal glory in Christ, after you have suffered a little while, will himself restore you and make you strong, firm and steadfast” (1 Peter 5:10). James considered believers who remain steadfast “blessed” (James 5:11).
Having a steadfast heart is a quality of someone who trusts God under all circumstances. Such a person’s life reflects the confident inner conviction that God is sovereignly in control over everything. The New Living Translations renders Psalm 108:1 like so: “My heart is confident in you, O God; no wonder I can sing your praises with all my heart!” No matter how hostile the conditions or how menacing the enemy, a steadfast heart will find the courage to sing out praises to the Lord.
