Verify that the oven is turned off, Access select functions menu, Turn knob clockwise until sabbath option appears – Bosch Gas Ranges User Manual
Page 17: Turn knob to set oven temperature, Turn oven light on if desired (press light), Press start. oven starts after 5 seconds, Change the time format, Turn knob clockwise until time format is displayed, Press start, Turn knob to select 12 hour or 24 hour format
