In the rich history of canon law of medieval period the Decretum of Burchard from Worms, of the eminent bishop of this city (1000-1025), beforehand the clergyman of Mainz, takes the particular place. This work, named also Liber Decretorum, Collectarium canonum, and also Brocardus, realized between 1007 and 1022, significantly registered in the sequence of systematic collections of church acts (of German group) developed before the Edict of Gracjan. The complement and explanation of rules in the Church legislation, and simultaneously the execution of the Church reform was the aim of these private collections coming from Italy, Germany, Gaul and Spain. The subject of the study is the Tome XV (De laicis) consisted of 44 chapters, in which several thematic topics can be distinguished enveloped – generally – around the idea concerning the relationships between the church authority and the laic authority (connecting of the state function with the Church function at that time). The analysis of the Tome XV of the collection indicates accenting by Burchard of the superiority of God’s law over the human law and the spiritual power over the earthly power.