Possible Clues:

• First day of Lent
• Beginning of Lent
• Tree named after German god Odin? Time to give up!
• Tree named after god of victory? Time to give up!
• Showed one's both loveless and light after a fast start
• It's time for high-church cleric to get the sack
• Fast start
• Dan, a shy Swede, resolved to repent then
• Date in church calendar Sweden, say, had relocated
• When a foreHEAD may be marked