This is one of the most important monuments of the Anglo-Saxon era. Brooke devotes fifteen or more pages to it in his History of Early English Literature. Kemble, Grimm, Grein, and others in foreign countries have studied it laboriously, and edited it, and Baskervill and Cook, among our own countrymen, have edited it either in full or in part.
In some aspects, Andreas is closely allied to the heroic poetry of the Anglo-Saxons, reminding us of Beowulf; in others, it is highly typical of the religious poetry of the oldest English period. Jacob Grimm said that, next to Beowulf, Andreas and Elene are the oldest and most instructive productions of Anglo-Saxon poetry.
The authorship and date of Andreas are both unknown. Grimm suggested Ealdhelm, bishop of Sherborne, who lived about A.D. 700. Grein, Deitrich, ten Brink, Gollancz, and others have assigned it to Cynewulf, who is thought to have lived in the eighth century. Sievers, Fritzsche, and Brooke think this poem was written by some imitator or follower of Cynewulf, which would probably put it in the early part of the ninth century. Professor Thomas Arnold regarded it as a West-Saxon poem of the eighth century.
The most definite theory of authorship is this: The Fates of the Apostles (Gr.-Wülk. Bibliothek, II, pp. 87-91) is the epilogue to the Andreas, and contains the signature which Cynewulf put in Elene, Christ, and Juliana, and the lack of which has kept scholars hitherto from feeling certain of Cynewulf's authorship. Brooke, after weighing all the arguments brought to bear by Gollancz to support this theory, dismisses it as "a happy suggestion," but not proved.
The source of the legend is the Acts of Andrew and Matthew in the Acta Apostolorum Apocrypha. An Anglo-Saxon prose version of the legend can be found in Bright's and in Baskervill and Harrison's Anglo-Saxon Readers. Zupitza's theory is that both the prose and the poetical versions are based, not upon the Greek, but upon a lost Latin translation of the Greek legend. This theory is quite generally accepted by scholars....
....The story is as follows: Matthew is in prison among the Mermedonians, a race of cannibals, who are waiting impatiently for his appointed day to come. To Andrew, who is laboring in Achaia, the command is given by God to go to his brother's (sic) aid. After parleying with the Almighty, Andrew goes to the seashore with his disciples, where he finds a vessel all ready and manned by three sailors. They agreed to take him and his disciples to Mermedonia with them. Long conversations take place between Andrew and the principal sailor, who is none other than God himself, though the apostle does not know it. Andrew is miraculously fed, and, after sailing a considerable distance and meeting stormy weather, he and his young men are miraculously transported to Mermedonia, and laid by the city walls. Christ appears to him in the form of a young man, promises him support, and escape from the cannibals. Then Andrew enters the city, miraculously gains entrance into the prison, and rescues Matthew and two or three hundred other captives. The devil appears upon the scene, and stirs up hatred against Andrew. The apostle is reviled and tortured by the multitude and by seven devils, but is saved and restored to bodily soundness by God's intervention. By stupendous miracles, the cannibals are converted to Christianity. A church is built, a bishop consecrated, and a regular organization perfected among these once cruel and barbarous but now gentle and pious people. After a few days, the apostle bids adieu to his dear converts, who, weeping and wailing, follow him to the shore, and sing a doxology as he embarks on his journey to Achaia, where "he life-departure, violent death endured."
— Judith, Phœnix, and Other Anglo-Saxon Poems