Building a Bridge with Beams of the Sun

Concerning the sunbeam lines from the Bitter Withy:

Our Saviour built a bridge with the beams of the sun,
And over He gone, He gone He;

Although I've read online that this story of Jesus walking on a bridge of sunbeams comes from one of the infancy gospels, I haven't found the source online, except for a selected passage cited on a webpage titled The Childhood of Christ, hosted by Maryville College:

Christ and riding on a sunbeam: Text? (See under Bodleian Ms. Selden supra 38 ). See also, K. v. Tischendorf, Evangelia Apocrypha (Hildesheim, Georg Olms, 1966; photoreproduction of the 1876 edition) p. 106, note 1 (In Tischendorf's edition of Pseudo-Matthew): Sequitur hoc loco in codice B narratiuncula quae abesta cdd. A et B. Est autem haec: Et cum Iesus cum aliis infantulis super radios solus (? solarii ? Scriptum est sol') ubique plures ascenderet et sederet, multique simili modo facere coeperunt, praecipitabantur, et eorum crura frangebantur et brachia. Sed dominus Iesus sanabat omnes. (Once, Jesus sat and rode up on a sunbeam many times, while he was with other children. Many of them wished to do the same thing and they fell; they broke legs and arms. But the Lord Jesus healed all of them -- Cartlidge.)

This story is pictorially depicted in the 14th-century Anglo-Norman Holkham Bible Picture Book, which is housed in the British Museum. An online text (pdf) provides the details:

THE HOLKHAM BIBLE PICTURE BOOK
M.S. Add. 47682

'THE HOLKHAM BIBLE PICTURE BOOK' is probably the most remarkable manuscript surviving from the second quarter of the fourteenth century. Formerly in the Holkham Hall Library it is now in the British Museum.

The purpose of this manuscript is revealed on its first page, which discloses a preaching friar commissioning a secular artist and explaining that the book is to be shown to rich people.

The lighter vein introduced into some of the illustrations is irresistible, and the most delightful example is perhaps the pictorial representation of the Infant Christ sliding down a sunbeam and miraculously excelling His playmates in other ways. The explanatory text was written in Norman-French but certainly in England, for when the shepherds at Bethlehem hear the angelic 'Te Deum' they break into English.

Here is the story of man's creation and of man's loss of paradise told in pictures by a master of illumination, and this facsimile of the manuscript should be a delight to collectors of fine books, historians, theologians and other scholars.

The costumes, tools, weapons and buildings in the pictures are those of fourteenth century England. They were intended as "visual aids" for a popular preacher to show to wealthy merchants or craftsmen. They present a medieval panorama by almost cinematographic methods. Many early occupations such as dyer, smith, carpenter, midwife are shown in what are virtually "stills" of a medieval miracle play of 1330 showing the England into which Chaucer was born.

Although this introduction states that the image presents Jesus sliding down a sunbeam, the later description states that he slides down a rainbow:

Frame 29

fol.15v. Five infancy miracles. When the Virgin washes Christ's clothes balsam trees grow. Healing the boy who fell from an upper room when at play with Christ. Walking on water, sliding down the rainbow and banging pots together at the well. The other children fail disastrously always, but Christ mends all.

Unfortunately, the images are not given online.

According to Ayers Bagley, of the University of Minnesota, who has a website titled Jesus at School, the British Museum houses the Tring Tiles, a series of tiles (originally part of Tring Church) with imagery depicting the childhood of Jesus. Unfortunately some of the tiles have been lost:

Although the Tring tile series is incomplete, enough of it is extant to reveal correspondences with illuminations in manuscript of the same time. Entitled Enfancie de Nostre Seignour, this work is thought to be the most fully illuminated infancy gospel still extant. Rhymed in couplets, the text relates Jesus' childhood acts. These may be characterized on a scale ranging from harmless to horrendous. Some of Jesus' deeds are beneficent. He heals the lame. He multiplies a harvest and distributes the surplus to the poor. Other of his acts are simply marvels. At his touch, man-eating lions become tame as tabby cats. Beneath his hand, clay sparrows become animate, take wing, and soar aloft. He can walk up a sunbeam or slide back down. He can, but other children cannot. When they try, they fall and break their pales. Some texts suggest that Jesus tempted children to follow him, intimating that he could foresee the consequences.

Not being familiar with either these Tring Tiles or the Enfancie de Nostre Seignour, I don't know if Bagley means that the sunbeam image appears on one of the tiles or only in the Enfancie book.

If the image of Jesus walking on a sunbeam appeared in Medieval English churches, then finding a source for the Bitter Withy song perhaps becomes easier.