|Saint Andrew, Apostle
The Holbein drawing at left features the four common identifying characteristics of portraits of St. Andrew: the wild hair, the long beard, a cross, and a book. (However, it is unusual for all four characteristics to be together in the same portrait.)
Wild hair is an individualizing characteristic of St. Andrew portraits from at least as early as the 6th century (example) to as late as the fifteenth (example). In the hagiography, I have not yet found any direct description of the saint's hair, but perhaps there is a connection with his conversation with Christ about the the latter's promise, "a hair of your head shall not perish" (Luke 21:18). In any case, medieval and later artists tend to give the saint a more manageable haircut (example).
As for the beard, most medieval and later images tend to show it as a good deal longer than the one shown at left, and somewhat less forked (medieval example, 15th-century example, 16th-century example). In early images, the beard is not long at all (example).
The cross is important in the Andrew hagiographies. Not only do they have him die on a cross, but they report lengthy disquisitions on his part explaining the mystery of the Cross. These sermons continued even while he was on his own cross when he was crucified in Achaia, to the awed inspiration of the crowd. (See Corona's painting of the event and the mosaic portrait in St. Paul Outside the Walls where the scroll he holds says that he prayed to the Lord while on the cross.)
The cross seen in the portraits is usually large enough to hold a man, as it is in the Holbein at left and in this fresco from Croatia of about the same period in the 16th century. The fresco uses the style of cross seen in older portraits, a simple † like Christ's. The X shape, called the "cross saltire" goes back at least as far as the 15th century (example). It refers to a later tradition that Andrew did not feel worthy to be given a cross like Christ's. The tradition could perhaps be influenced by the story of St. Peter's crucifixion upside-down. In a 15th century Catalan altarpiece the Achaians seem to be crucifying him sideways!
As an apostle St. Andrew is also commonly shown with a book. Just before his death on the cross in the Golden Legend account, he speaks of his yearning for "the purity of contemplation," and a contemplative emphasis may be behind the way he seems to meditate on his book in the Isenbrant Crucifixion and even the monkish garments he wears in some portraits (example).
The subjects for narrative images of St. Andrew include his crucifixion, his calling by Christ (example) as related in Matthew and Mark, the legendary episodes from his years as a preacher, and miracles effected in his name.
Feast day: November 30
Statue in the Lateran Basilica, 1708-09Other Narrative images:
Painting of his crucifixion, early 16th centuryAlso see:
Golden Legend #2: html or pdfScripture:
The Acts of Andrew (cached)
The Acts of Andrew and Matthias (cached)
The Acts of Peter and Andrew (cached)