Because I noticed so many things, I'm going to go through the tune phrase by phrase.
The first phrase:
In the second verse, the text here is "As twilight hovers near at sunset." It's a small point, but "sunset" is sung to a descending phrase (if two notes constitute a phrase): F E. Musically, this gives something of a sense of the sun's setting.
In the third verse, the text here is "In all life's brilliant timeless moments." Here, "all" and "timeless" are sung with melismas ("all" to A Bb and "timeless" to F G D). Because of these articulations, there's a sense of the breadth of "all" and the prolonged nature of "timeless."
The second phrase:
In the second verse, the text here is "And lamps are lit, and children nod." Similar to the descending "sunset" earlier in the verse, "children nod" is sung to a descending phrase (G F E), giving a sense of their "nod[ding]" and falling asleep.
The third phrase:
Musically, this is the same as the first phrase, but I wanted to format it differently to point out the cross inscriptions. There's a connection between the cross inscription(s) and the third line of the third verse: "O Son of God, our Life-bestower." "Life-bestower" (sung to the five notes that form two cross inscriptions) could be taken simply in the sense that God created us, as Psalm 139:13 states: "For you formed my inward parts; you knitted me together in my mother's womb." In conjunction with the cross inscription(s), however, there's also the sense of God's giving us life through Jesus' crucifixion and resurrection. John 3:14-15: "'And as Moses lifted up the serpent in the wilderness, so must the Son of Man be lifted up, that whoever believes in him may have eternal life.'"
Similar to the melisma'd "timeless" in the first line of the third verse, the text in the third line of the first verse ("Pure gleam of God's unending glory") has a melisma'd "unending" (G F G D). It's stretched out, which gives something of a sense of the word's meaning.
In the second verse, the line here is "In evening hymns we lift our voices." "Lift" is sung with an ascending melisma (F to G), musically giving a sense of the word's meaning.
The fourth phrase:
Like the melisma'd "timeless" and "unending," in the fourth verse, there's a melisma'd "endless" (D F E) in this phrase ("Whose glory lightens endless days").
