Hi, Haruo - I thought I might find something in an old Lutheran hymnal, but no dice. I did find this (click) at the Robokopp site, a 1912 Wisconsin synod hymnal, all in German (robokopp is in Kenosha, so it's a natural).
I looked in a 1917 hymnal from the United Lutheran Church in America, and found one that goes like this:

Now that the sun is beaming bright
Once more to God we pray
That He, the uncreated Light
May guide our souls this day.

No sinful word, no deed of wrong,
Nor thoughts that idly rove
But simple truth be on our tongue
And in our hearts be love

And while the hours in order flow
O Christ securely fence
Our gates, beleaguered by the foe
The gate of every sense

And grant that to thine honor, Lord
Our daily toil may tend
That we begin it at they word
and in thy favor end.

The hymnal says the lyrics were written by Samuel Howard, 1762
Melody is Lancaster, c.m.

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Note the following hymn at Cyberhymnal:


Now that the daystar glimmers bright
We suppliantly pray
That He, the uncreated Light,
May guide us on our way.

No sinful word, nor deed of wrong,
Nor thoughts that idly rove,
But simple truth be on our tongue,
And in our hearts be love.

And while the hours in order flow,
O Christ, securely fence
Our gates, beleaguered by the foe,
The gate of every sense.

And grant that to Thine honor, Lord,
Our daily toil may tend;
That we begin it at Thy Word,
And in Thy favor end.

To God the Father glory be,
And to His only Son,
And to the Spirit, One and Three,
While endless ages run.



Words: Attributed to Ambrose of Milan (Iam lucis orto sidere); translated from Latin to English by John Henry Cardinal Newman, 1842.

Does this the same source as "Nun is sie erschienen"? Seems to me that it well could be. Then again, maybe not. There are parallels in the first and second verses.