Shared ground
Psalm 92:15 functions as the psalm’s closing summary. The verse explicitly says the outcome is “to show” something about Yahweh’s character. It then makes three linked claims: Yahweh is “upright,” Yahweh is “my rock,” and there is no “unrighteousness” in him. Together they present God as morally straight and personally reliable.
“Upright” is not just a feeling; it is a claim about what God is like in how he acts. “My rock” is also a claim, using a stability-and-refuge image to describe the speaker’s trust in God. The final line is stated as an absolute denial of wrongness in God.
Where interpretation differs (only where needed)
Some readers take “to show” mainly as public witness: the psalm’s message (including the flourishing of the faithful in the wider psalm) is meant to make God’s character visible to others. Others hear it mainly as reassurance: the psalm’s conclusion is meant to settle the worshiper’s own doubts when circumstances look unfair.
There is also some difference in emphasis on “upright.” For some, it highlights moral purity (God never does wrong). For others, it highlights dependability (God is straight, not crooked, in the way he governs and keeps promises). Many interpreters treat those as overlapping rather than competing.
Why the disagreement exists
The wording is brief and can carry more than one emphasis. The verb “to show/declare” can fit a public setting (temple worship) and also fit a personal conclusion drawn from lived experience. Likewise, “upright” can describe both moral goodness and practical reliability, and the “rock” image can point to safety, steadiness, and faithful protection.
What this passage clearly contributes
This verse explicitly anchors the psalm’s whole message in God’s character, not in changing circumstances. It contributes a strong claim about God’s moral integrity (“no unrighteousness in him”) and a relational claim (“my rock”), holding together God’s objective goodness and the speaker’s personal reliance. It also frames praise and testimony as having a purpose: making God’s uprightness known (whether primarily to the community, to observers, or as settled conviction in the worshiper). See also Deuteronomy 32:4 for similar “rock” and “no wrong” language.
