It's sung to the tune "O Jesu Christe, wahres Licht," which is more or less the same title in German: "O Jesus Christ, true light." Here's the first musical phrase:
In the fifth verse, the text here is "That they with us may evermore...." (The "they" is "all those who walk apart" from the previous verse.) "Evermore" is sung with a melisma (the last four notes). Because the word is stretched out, there's something of a sense of its meaning.
There's a similar feature with the third musical phrase:
Still in the fifth verse, the text here is "And endless praise to You be giv'n." This time, "praise" is sung with a melisma (the A and G in the second measure). Because there's an extra syllable, there's something of a representation of the praise's being "endless."
