Back then, candles would have been made from either beeswax (churches and rich people) or tallow (everyone else). Spermaceti and brassica-oil candles were not yet in common use. The median family spent 65 shillings per year on candles. The total value stolen was 49.5 shillings. So a valid comparison would be 75% of the median family's annual lighting budget today. I estimate the annual cost for lighting at 1000 kWh grid power (US$120, GB£80), plus some replacement compact fluorescent bulbs (US$30, GB£20), for a crime equivalent of US$113 or GB£75.

Another valid comparison would be the amount it would cost for an equivalent amount of lighting now. In modern terms, the items stolen amounted to about 800 hours of a one-candela light source. Maybe one green 20mW LED and 6 AA alkaline (LR6) batteries, or a white LED and 6 D alkaline (LR20) batteries. This is equivalent to the light of leaving one 25W compact fluorescent bulb on for 6 hours.

Imagine if every time you left the light on in your bedroom when you left for school, your Dad killed you, and then danced on your grave, singing 'alleluia.