In substance the Acts are a religious novel, similar in form, and to some extent in matter, to the Greek romances by Achilles Tatius, Heliodorus, and others, and based upon the belief that St. Paul actually did visit Spain, according to the intention expressed by him in Romans xv.24. The editor of the Greek text is inclined to assign its composition to about the middle of the third century, reasoning from its relations to the Acts of Paul, and those of other apostles, which its author apparently knew and made use of. Thus a knowledge of the Acts of Paul and Thecla may be inferred from c. xxvi., of the Acts of Peter from c. xxiv., and of those of Andrew from cc. xxviii.-xxxi.
The first and longest part of the story (from c. i. to xxi.) gives an account of the conversion of Xanthippe, wife of Probus, a man of rank in Spain. In this part the narrative is less prominent than the speeches and prayers, which are numerous, and of considerable length. With c. xxii. a new section of the story begins, of which no previous warning has been given except in the title, containing the adventures of Polyxena, the sister of Xanthippe, who is carried off in the latter's absence. The rest of the story is much more diversified than the early part, being full of incident and introducing a great variety of persons -- the apostles Peter, Philip, and Andrew, an ass-driver, the Jewess Rebecca, a wicked prefect and his kind-hearted son, and finally Onesimus, who brings Polyxena back to Spain.
This difference in the character of the narrative in the two parts causes also some difference in the language, which in the earlier section is more diffuse and more difficult of exact translation than in the later one. The meaning of some words is also doubtful: those translated "lamp-stand" and "destroyer," towards the end of c. xxi., are so rendered in accordance with suggestions by his Exc. M. Gennadius, who also characterises the language of the text as full of errors.