What is the ruling on refraining from work on Sunday if the market is closed, even though some consider this an imitation of disbelievers, despite that not being the intention of the workers?

If leaving work on Sunday is due to there being no need for work, then there is no harm in it. However, if the intention behind leaving work is to venerate this day because it is a holiday for non-Muslims, then it is impermissible, because it constitutes imitation of them. Sheikh al-Islam Ibn Taymiyyah mentioned that among the innovations is to abstain from work on this day and to make it a day of rest, joy, and play. The guideline is that nothing specific should be innovated on this day; rather, it should be treated like any other day. Muslims are advised to work on this day and on other days of the polytheists' holidays so that doctrinal distinctions do not fade away.