"On Christ's Ascension I Now Build"

When I transcribed "On Christ's Ascension I Now Build" a few months ago, I noticed that - like a lot of hymns about the Ascension - lines that mention the Ascension are sung to ascending phrases.  "On Christ's Ascension I Now Build" is sung to the tune "Nun freut euch," the first two phrases of which are:

In the first verse, the text sung to these phrases is "On Christ's ascension I now build / The hope of my ascension," and in the third verse, "O grant, dear Lord, this grace to me, / Recalling Your ascension."  All of the "ascension"s in these lines are sung to groups of ascending notes.  The "ascension"s at the end of the second phrase are even sung with melismas, with the extra syllable emphasizing the ascending melody.