He was there in the wilderness forty days.@Mark 1:13
Gregory I (540–604)

Attributed to Gregory I, 6th Century (Clarum decus jejunii); translated from Latin to English by Maurice F. Bell in The English Hymnal (London: Oxford University Press, 1906), number 68.

Spires from Geistliche Lieder, by Joseph Klug, 1543; harmonized by Johann S. Bach (🔊 pdf nwc).

Johann S. Bach (1685–1750)

The glory of these forty days
We celebrate with songs of praise;
For Christ, by whom all things were made,
Himself has fasted and has prayed.

Alone and fasting Moses saw
The loving God who gave the law;
And to Elijah, fasting, came
The steeds and chariots of flame.

So Daniel trained his mystic sight,
Delivered from the lions’ might;
And John, the Bridegroom’s friend, became
The herald of Messiah’s name.

Then grant us, Lord, like them to be
Full oft in fast and prayer with Thee;
Our spirits strengthen with Thy grace,
And give us joy to see Thy face.

O Father, Son, and Spirit blest,
To thee be every prayer addressed,
Who art in threefold name adored,
From age to age, the only Lord.