Council of Epaone
The Council of Epaone or Synod of Epaone was held in September 517 at Epaone (or Epao, near the present Anneyron) in the Burgundian Kingdom. It was one of three national councils of bishops held around that time in former Roman Gaul: the council of Agde was held in 506 in the Visigothic Kingdom in the south and the council of Orléans in 511 for the Kingdom of the Franks. The synod enacted the first legislation against wooden altars, forbidding the building of any but stone altars. It also witnessed to the rise of the practice of  mitigation of canonical penance in view of the changing times and social conditions of Christians. References. The fullest reference appears to be "The New Schaff-Herzog Encyclopedia of Religious Knowledge, Vol. IV: Draeseke–Goa" which includes facsimile images of the pages along with a searchable text version. The relevant data is on pages 149–150 and is reproduced below.