The second musical phrase (repeated later as the fourth musical phrase):
In the first verse, the text here is "Lord of all, we bow before Thee." The "all" is sung with a melisma (A G), giving a sense of number, and the "bow before Thee" descends, musically representing that "bow[ing]." The "bow" is also sung with a melisma (C Bb), emphasizing this.
In the second verse, the text here is "Angel choirs above are raising." The "above" is sung to an ascending interval (a minor third: A to C)(plus the following Bb), directing attention upwards. There's a similar feature in the fourth line of the first verse ("All in heav'n above adore Thee"), where "above" is again sung to these same notes. Usually, I probably wouldn't bother pointing out something this small, but - within each musical phrase - this minor third is the largest interval in the entire hymn. Everything else is extremely conjunct, with either repeated pitches or seconds upwards or downwards.
The fourth line of the second verse (also sung to this same phrase) is "In unceasing chorus praising." "Unceasing" is sung with a melisma (A A G A), and since the word is drawn out, there's something of a musical sense of its meaning.
The third musical phrase (a repetition of the first musical phrase):
In the third verse, the text here is "Prophets swell the glad refrain." "Swell" is sung with a melisma (F E), so - as with "unceasing" above - since the word is drawn out, there's a musical sense of its meaning.
The fifth musical phrase:
In the first verse, the text here is "Infinite Thy vast domain." "Infinite" is sung with a melisma (G A Bb A), musically giving a sense of that great expanse.
In the fourth verse, the text here describes how Jesus was "First to break the bars of death." "Break" is sung with a melisma now (Bb A). It's "broken" between two pitches, which musically illustrates the "break[ing]" in the text.
The sixth musical phrase:
In the first verse, the text here is "Everlasting is Thy reign." As with "Infinite" above, "Everlasting" is sung to a melisma (D D C Bb A), musically giving a sense of a long period of time.
In the third verse, the text here is "Through the Church the song goes on," with "song" sung to a melisma (Bb A). Since "song" is not limited to just one pitch, there's something of a musical representation of this "go[ing] on."
