Crux Fidelis is part of a larger work by Saint Venantius Honorius Clementianus Fortunatus (c530-c609) beginning Pange lingua ('Sing, my tongue'). He wrote it for a procession that brought a part of the true Cross to Queen Radegunda in 570.
Faithful cross, above all other,
One and only noble tree:
None in foliage, none in blossom,
None in fruit thy peer may be.
Sweetest wood and sweetest iron,
Sweetest weight is hung on thee!