Cast your burden on the Lord, and He shall sustain you; He shall never permit the righteous to be moved.
Psalm 55 is among many Davidic Psalms set in the context of conflict, but this time his adversaries are in his hometown (vs. 9-11) and among his friends (vs. 12-14). David had seen opposition from many quarters, but betrayal from within added a bitter dimension to his trials. His restlessness, hurt, and fear are on full display as the psalm opens (vs. 1-5), and the urge to escape overwhelms him (vs. 6-8). There are times in life when we can identify with David’s desperation and the urge to escape from life’s trials, but the psalm concludes with a better, more sure course of action: "Cast your burden on the Lord, and He shall sustain you" (vs. 22).
This verse is the focal point and crescendo of the psalm. David’s restless fear and the bitter opposition of his betrayers lead him to this conclusion, which is the only admonition of the psalm. Throughout, David is addressing God (vs. 1, 9, 23), but it is as though he pauses in his prayer to glance our way and offer this life-changing lesson that he has learned by hard experience: "Cast your burden on the Lord, and He shall sustain you."
The translation "burden" in NKJV, and "cares" in NIV, are too limited for the Hebrew word which means "lot," or whatever is appointed to you, with a more comprehensive view of life than just its burdens. Thus we are encouraged to cast our very lives upon the Lord, seeking His refuge and guidance in all things. And, notice that the promise is not that God will dispel every fear and resolve every problem, but that He will sustain you. As David found out, escape is not the answer that God provides; what He does provide is the strength and grace to navigate the path ahead.
As important as this lesson is, an even greater reality looms behind it in this psalm. As a type of Christ, David’s experience is unique in that it portrays the suffering of our Lord on our behalf. The betrayal of a friend, described in vs. 12-14, was played out in Christ’s life, just as it is also depicted in Psalm 41:9. Even as David sees the whole city in an uproar against him (vs. 9-11), we cannot help but remember that the crowd of the same city cried out, "Crucify Him!" (Matt. 27:22). In these ways, Psalm 55 powerfully and prophetically depicts the bitterness that Christ endured for our salvation.
Christ exemplified the crowning lesson of this Psalm in the Garden of Gethsemane (Matt 26:36-46), where we see the outline of Psalm 55 unfold. First, Christ described His sorrow and fear, as David did. Then, He cast His burden on the Father in prayer, as David did. The Lord did not give Christ an escape from this dark hour of suffering, but He did give Christ the grace and strength to fulfill His calling and accomplish our salvation. Thus, the Lord Jesus Christ perfectly exemplified the admonition that this psalm lays upon us: "Cast your burden upon the Lord and He shall sustain you."