When I read the pericope from Haggai the phrase The latter splendor of this house shall be greater than the former, and for some reason I wondered what the word ‘splendor’ actually means. And when verse 5 of psalm 145 began: On the glorious splendor of your majesty, I decided I would go look it up. And it turns out that ‘splendor’ from Haggai 2:9 and come from the Hebrew kābôd, meaning: glory or honor; while ‘splendor’ from Psalm 145:5 comes from the Hebrew hādār meaning: glory, majesty, honor, beauty, beauty (which I was surprised to learn means: beauty etc), or excellency. Now that two different words have such similar meanings shouldn’t be a surprise, who hasn’t used a Thesaurus from time to time. Any way.
The New Interpreter’s Bible One Volume Commentary [i] and Study Bible [ii], both speak about the rebuilding of God’s house as central to Haggai’s prophecy. And central that the effort is not so much that the people have rebuilt their houses and fields, and not the Temple, but what that reality says about their relationship with God. They have put themselves and their priorities first and God second. That decision makes them unclean, unable to be in God’s presence. Rebuilding in essence is a form of ritual cleansing; and though the wealth will adorn the Temple it is God’s presence that will perfect it, that will cleans the people and restore them to relationship with God’s self.
All that being noted, I’m lean to the meaning of kābôd as honor, implying the people will honor God at this time, than they did in the time of the first Temple. A long way to say this has little to do with building magnificent structures and is truth is about building ever deepening relationships with God. In short, by yet another name, it’s salvation.