You're apparently also not that well versed in English idioms given that "doing the Lord's work" is a well-known phrase which does not need explaining to the average speaker (native or not) of that language.
Doing the Lord’s Work
When someone handles a task that benefits everyone — especially something inconvenient, uncomfortable, or ignored by others.
Often used humorously. Doesn’t always refer to religion.
Can describe someone sacrificing time, energy, or sanity to improve a situation nobody else wanted to deal with.
“Whoever fixed the Wi-Fi before the meeting started is doing the Lord’s work.”
They’re doing the lord’s work.