Among many religious people, there is an opinion that it is strictly forbidden to engage in any kind of physical labor and household chores on Sundays and on major church holidays, because it is considered a great sin.
This opinion is based in the Bible, where the last day of creation (in the Old Testament it was considered Saturday) was called a day of rest, a day dedicated to God. The Jews, for example, strictly observe the Sabbath (Saturday), according to the prescriptions of the Talmud, refraining on this day from any work and in general any active actions, the list of which is quite extensive.
For Christians, the "day of rest" became the resurrection - in remembrance of the Resurrection of Christ. Along with other major church holidays, this day is revered in the Church as a day of special triumph and joy, which must be dedicated to God - that is, spend, first of all, in deeds of love, mercy and prayer, and not in the vanity of everyday life.
This is largely due to the fact that before, almost any work, even the simplest, took a lot of time and effort. For example, in order to simply wash, it was necessary to melt the bathhouse (and this is a whole ritual) and, accordingly, take this time away from worship or something more useful, because they tried to do all this before the holiday.
However, of course, there is no canonical church prohibition on physical labor on holidays, and even more so, of course, there is no prohibition on self-care - these are nothing more than semi-pagan traditions of “folk Orthodoxy”.
For example, for some reason it is believed that on the indicated days it is impossible to sew and take a needle in your hands, since you can lose your eyesight, and on the Annunciation, women are "not recommended" to perform any manipulations with their hair, explaining this by various prophecies - from the loss of a loved one, before losing, in fact, the hair itself.
Thanks to these and other common superstitions, it often turns out that people are simply idly bored, not devoting time to any useful deeds in general, so that "God does not punish."
Working on holidays, of course, is not a sin, especially if this work is done with joy and for the good of others. And, of course, there is no need to forbid oneself any necessary work - on the contrary, it is better to allow oneself to "let" God and thoughts about Him into one's work.