“LORD, Your testimonies are completely reliable; holiness is the beauty of Your house for all the days to come.”
(Psalms 93:5 HCSB)

I love the HCSB translation here, especially “holiness is the beauty of your house.”

Beauty is the thing that stands out about something that we remember because it strikes us so deeply.  The beauty of the rose is in the combination of its startling color—red, yellow, white, etc.—and its fragrant smell.  The beauty of a mountain landscape is in the sheer magnificence of all that our eyes take in, mountains, skies, snow, sun, pines, and wildflowers.  We remember beauty.

Here the psalmist says that it is God’s holiness that is the beauty of His house.  His holiness stands out as remarkable and exceptional and awe-inspiring.  This is true now, it is true in the days to come, it is true for all eternity.