In the fourth verse, the text here is "Christ with His people evermore remaining." "Remaining" is sung with a melisma (B C B A), and since it's stretched out, there's a sense of the duration of "evermore."
The third musical phrase:
In the third verse, the text here is "To win disciples out of ev'ry nation." "Nation" is sung with a melisma (A G F), giving a sense of amount, for "ev'ry."
In the fourth verse, the text is "Christ to all ages gloriously reigning." Similar to the above, "ages" is sung with a melisma (C Bb A), giving a sense of the entirety of "all."
In the fifth verse, the text is "Filled with His Spirit, love and pow'r receiving." Here, "Spirit" is sung with a melisma (C Bb A), giving a sense of the abundance that "filled" implies.
[I re-used notation excerpts I made for writing about "Lord of Our Life," which is sung to the same tune. Both appear in the same key in The Lutheran Service Book, although the bar lines appear in different places. "Lord of Our Life" #659 has four beats per measure where "Christ High-Ascended, Now in Glory Seated" #840 has eight.]
