This is an old song. The melody was by J.S. Bach, who is probably the most well known composer of all time. Words are by Bernard of Clairvaux.

Lyrics:
O sacred Head, now wounded, with grief and shame weighed down,
Now scornfully surrounded with thorns, Thine only crown;
How pale Thou art with anguish, with sore abuse and scorn!
How does that visage languish, which once was bright as morn!

What language shall I borrow to thank Thee, dearest friend,
For this Thy dying sorrow, Thy pity without end?
O make me Thine forever, and should I fainting be,
Lord, let me never, never outlive my love to Thee.