He became the patron saint of lost things after praying for the recovery of a stolen book of psalms. That's not his only gig though, other events in his life led to him being named the patron saint of amputees, Brazil, the elderly, shipwrecks, poor people, oppressed people and more
According to a statement shared by Bishop Seitz, Canon 87 §1 of the Code of Canon Law allows bishops to dispense the faithful from universal church laws “whenever he judges that it contributes to their spiritual good.”