Passage
Thy righteousness is an everlasting righteousness, and thy law is truth.
Thy righteousness is an everlasting righteousness, and thy law is truth.
Psalms 119:140 Thy word is exceeding pure, and thy servant loveth it.
Psalms 119:141 I am little and despised: thy precepts have I not forgotten.
Psalms 119:142 Thy righteousness is an everlasting righteousness, and thy law is truth.
Psalms 119:143 Trouble and anguish have taken hold upon me: thy commandments are my delights.
Psalms 119:144 The righteousness of thy testimonies is for ever: give me understanding, and I shall live.
The verse centers on "righteousness", "everlasting", and "truth". It is saying that the verse draws attention to "righteousness" and "everlasting", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 141's "I am little and despised thy precepts..." into verse 143's "Trouble and anguish have taken hold upon...", so "righteousness" and "everlasting" 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 "righteousness" and "everlasting" with trust shaped by these words, not by a vague optimism outside the passage.