But is that a reference to the Bible? "To earn (my/your) daily bread" is a set phrase in English
and many other European languages (French pain quotidien etc) as well.
You might be surprised how many of the common aphorisms you use every day come from the Bible. Ever gone the extra mile? Moved mountains at the eleventh hour to get to the root of the matter? Ah well, no rest for the wicked, it's like the blind leading the blind.
[1] https://el.wiktionary.org/wiki/%E1%BC%94%CF%80%CE%B5%CE%B9%C...