The discovery of 85 written records of judicial oaths and instructions for the perjurers, deposited in the archival fund of Ljubljana diocesan seigneury (Pfalz Laibach) in Ljubljana Archiépiscopal Archive, can be characterized as exceptional. It is not only the matter of the second largest complex of the older Slovene documents of the same provenience, originating from the second decade of the 19th century, but with this discovery the number of all, up till now known judicial oaths in the Slovene language, has grown by as much as one third. The particular worth of the judicial oaths, published in here, lies in their contents. In addition to the introductory and concluding wording formula, each judicial oath in itself is an original text written in Slovene, the subject matters of the testimony are very heterogeneous, on the other hand the judicial oaths as a whole, offer diverse lexical wealth of words. Moreover, they are a very direct reflection of the development of the spoken and written Slovene language of the second half of the 18th and the beginning of the 19th century, and some sort of a standard criterion for the transmission of the literary language and the only hardly emerging official language, into the case law.