I had to sign something like that also in 1994 when I entered Bethel.
It was STRESSED to us that we could not do any secular work while at Bethel (except on our holidays) We only got 1 day holiday for every month worked. ie so 12 days in total each year.
I did not have family with money to support me, so I had to use all my vacation days to do work window cleaning just to pay the expenses of running a car. (We got a small vehicle allowance but it wasn't enough to cover costs) And we couldn't live without a car here in that part of Sydney
But some Bethelites had secret jobs after hours (like in a petrol station). When it was found out, they would be severely disciplined.
It all seems so culty and high-control now. But back then we thought it was normal!