FERIAE IN IUDICIIS. — On certain days of the year, procedural acts cannot be undertaken. These dies feriati or feriae are divided into: 1) ordinary, which are strictly established in the CIC (can. 1639: precept feasts and the last three days of Holy Week) and extraordinary, established by competent authorities for special events (anniversaries of the Pope’s election, of the Lateran Pacts, etc.); and 2) of common law (established for the whole Church) and of particular law (established by individual ordinaries, can. 1638 § 1).
Current law, unlike the decreta, regards procedural acts performed on ferial days as illicit but not invalid. In individual cases justified by necessity, Christian charity, or the public good, can. 1639 permits the judge to perform such acts on ferial days; normally, however, pursuant to can. 1635, there is a de iure prorogation to the next non-ferial day.