For halocho purposes, what is the difference between an “invalid” and a “choleh she’eyn bo sakonoh”
Answer:
For somebody who is ill (though not in danger) a number of halachic leniencies apply, for instance in the obligation to fast on fast days (other than Yom Kippur and Tisha Be’Av), using medicines on Shabbos, and so on. An ‘invalid’ is not necessarily somebody who is ill, and the various leniencies that apply to somebody ill may or may not apply, depending on his condition.
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