Passage
Cast thy burden upon Jehovah, and *he* will sustain thee: he will never suffer the righteous to be moved.
Cast thy burden upon Jehovah, and *he* will sustain thee: he will never suffer the righteous to be moved.
Psalms 55:20 He hath put forth his hands against such as are at peace with him; he hath profaned his covenant.
Psalms 55:21 Smooth were the milky [words] of his mouth, but his heart was war; his words were softer than oil, yet are they drawn swords.
Psalms 55:22 Cast thy burden upon Jehovah, and *he* will sustain thee: he will never suffer the righteous to be moved.
Psalms 55:23 And thou, O God, wilt bring them down into the pit of destruction: bloody and deceitful men shall not live out half their days. But as for me, I will confide in thee.
The verse centers on "cast", "burden", "upon", "jehovah", "sustain", "thee", "never", and "suffer". It is saying that the verse draws attention to "cast" and "burden", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 21's "Smooth were the milky words of his..." into verse 23's "And thou O God wilt bring them...", so "cast" and "burden" belong inside that flow. In Psalms context, the local focus is worship, trust, the LORD's kingship, and covenant mercy.
A plain takeaway is to answer the verse's own emphasis on "cast" and "burden" with trust shaped by these words, not by a vague optimism outside the passage.