Passage
Oh let the house of Aaron say, “His lovingkindness endures forever.”
Oh let the house of Aaron say, “His lovingkindness endures forever.”
Psalms 118:1 Give thanks to Yahweh, for He is good; For His lovingkindness endures forever.
Psalms 118:2 Oh let Israel say, “His lovingkindness endures forever.”
Psalms 118:3 Oh let the house of Aaron say, “His lovingkindness endures forever.”
Psalms 118:4 Oh let those who fear Yahweh say, “His lovingkindness endures forever.”
Psalms 118:5 From my distress I called upon Yah; Yah answered me and set me in a large place.
The verse centers on "house", "aaron", "lovingkindness", "endures", and "forever". It is saying that the verse draws attention to "house" and "aaron", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 2's "Oh let Israel say His lovingkindness endures..." into verse 4's "Oh let those who fear Yahweh say...", so "house" and "aaron" 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 "house" and "aaron" with trust shaped by these words, not by a vague optimism outside the passage.