The First Council of Toledo was convened to deal with divisions among the Spanish episcopate caused by the conviction and execution of Priscillian in 385. Many people in Spain, the bishops among them, considered the judgement unfair and venerated Priscillian as a martyr. The acts of the council consist of the twenty canons with the preface and the subscriptions of the bishops, the creed (regula fidei) with 18 anathemas against Priscillian, the professions of faith declared by the former adherents of Priscillian and the closing sententia definitiva. The last two are excerpts from the full version of the conciliar acts which has not survived and has been transmitted in the manuscript tradition separate from canonical collection of Hispana (Chadwick 1976: 179-181; Burrus 1995: 104-105).

The date of the council is given in the beginning of the preface - it is the time of Arcadius and Honorius (then between 395-408) and of the consulship of Stilicho (400 or 405). The date given in the Spanish era is unreliable, because a lot of different versions survived in manuscripts. G. Martínez Díez and F. Rodríguez (1984: 326) thought that it was a later addition. Moreover, Ambrosius of Milan and Siricius are both already dead (the title sanctae memoriae is added before their names), therefore the council must have been held after 399. Also Hydatius in Chronicle dates the council to 400, so this is the most probable solution (Weckwerth 2004: 89-90).