Numbers 23:19
The context
Balaam has been hired by Balak to curse Israel, and instead blessings keep coming out of his mouth. This verse is part of his reply to the king's frustration, and it contrasts divine constancy with human unreliability. The oracles are set at altars overlooking the camp.
What it establishes
It establishes that God's word is treated as more reliable than human speech, and that his intention toward those he has blessed does not shift with circumstances. The contrast is between changing and not changing.
What it does not establish
It sits in tension with other texts. Several passages describe God relenting or changing a stated course, and how that is reconciled with this verse is a longstanding problem. The line is an oracle in a narrative, not a philosophical definition of impassibility.
Short note, first pass, October 2026. Corrections welcome.
Cited in these answers
Part of Scripture, Opened — the exegetical layer behind every citation on this site. Scripture quotations are from the ESV.