The instruction, written by Primate Zbigniew Oleśnicki the Younger on the occasion of his visit to Gniezno scheduled for March 1482, includes instructions for the clergy on the celebration of sacraments, instructions on the procedure used by church courts and a detailed questionnaire for visitors. The document, although published in print at the beginning of the 20th century, was barely noticed by researchers of the history of the Church in Poland. The manual addresses and raises several problems typical of social conditions in Poland in the second half of the 15th century. The questions included in the visitation survey indicate a lack of discipline among the clergy and abuses towards the faithful (e.g. charging excessive fees), as well as cases of unfair promotion to church positions (the latter was facilitated by the spread of patronage of influential laypeople over benefices). Z. Oleśnicki the Younger also takes action against the unwritten privileges of the nobility in the field of church discipline - in particular against exemptions from church prohibitions. Attention is drawn to the precise list of rights and circumstances that may serve to defend a suspect in court proceedings, as part of the general presumption of innocence. In the text of the Instruction, numerous examples of tolerance towards people of other faiths can be noted - such as, for example, the admission of Czech scholars to Polish schools from which they were previously excluded as Hussites. The Instruction of Z. Oleśnicki the Younger is a work that independently interprets common law. Strict dependence on Polish synodal statutes is visible only in a few places.