Johann Scheffler's (Angelus Silesius) poem "Ich will dich lieben, meine Stärke" can be found in almost all German hymnbooks - with quite a few different melodies. Scheffler puplished it in 1657 in his collection "Heilige Seelen-Lust".
The first two verses are a declaration of love - twelve times "I will love you" is said. A rough translation of the first vers is this:
I want to love you, my strength,
I will love you, my ornament,
I will love thee with the work
And everlasting desire;
I will love you, most beautiful light,
Until my heart breaks.
The acceleration wasn't intended, so I did some more takes... each getting more boring and sounding more stressed... So I stick to this first version. I hope you like it!