Pope Gregory is the Gregory
of gregorian chant, however
he wrote the words for 
Father, We Praise Thee, 
 Now the Night is Over,
 and the tune Christe Sanctorum
is anonymous.

Gregory the Great

The words were written by Pope Gregory I
Yes, prelates have been songwriters.
St. Gregory was the Bishop of Rome (aka. Pope) from September 3, 590 until his death on March 12, 604. He was born into a wealthy, empowered family of Rome, but the Plague of Justinian caused famine and tragedy when he was about two. When he was about six, Rome was sacked, and almost the entire population was destroyed or became refugees.
We do not know what happened to him and his family, but they had estates in Sicily.
In his time, he saw the Franks, Goths, Visigoths acquire Christian trappings. The capital of the Roman Empire was at Constantinople, and the Roman popes were required to have the approval of the Byzantine Emperor.

"Father, We Praise The, Now the Night is Over", is an
early morning prayer of gratefulness to God's care.

What we have to offer, in gratefulness, is prayer and
meditation.

The hope of this poem is that the God who watches over us
through the night and watches us while we sleep, will fit
us, and make us whole so that we can experience heaven.

This poem connects us to those who by virtue of having
already passed from life, are experiencing  joy unending.

It is definitely Trinitarian, specifically mentioning the
Father, Son and Spirit.

Father, We Praise Thee, Now the Night is Over

Father We Praise Thee

Gregory the Great

Father, we praise Thee, now the night is over;
Active and watchful, stand we all before Thee;
Singing we offer prayer and meditation:
Thus we adore Thee.

Monarch of all things, fit us for Thy mansions;
Banish our weakness, health and wholeness sending;
Bring us to heaven where Thy saints united
Joy without ending.

All-holy Father, Son and equal Spirit,
Trinity blesses, send us Thy salvation;
Thine is the glory, gleaming and resounding
Through all creation.

Meter: 11.11.11.5

ST SONG