According to a common custom among Ashkenazim, a man only starts wearing a tallis while davening after he gets married. Does a divorced man continue to wear a tallis when davening? Or could/should he stop wearing the tallis, so as not to give the impression that he is still married?
Excellent question. Greetings and welcome to J.SE!
German and Sephardic Jewish men begin wearing a Tallis many years before marriage; the question if anything is why those of Eastern European ancestry wait until marriage.
I'm told that once a man gets married and starts wearing a Tallis, the practice (I wouldn't say "must", but certainly "normative practice") is to continue doing so (hey every fringed four-cornered garment you wear is a mitzva), even if he's no longer married.
Yes this gets confusing; it means that someone wearing a Tallis in shul may not be married -- he could be previously-married, or for that matter he could be Sephardic or "Yekkish" (of German ancestry). But if he's not wearing a Tallis, he's definitely single. (Or he just forgot his Tallis that day, I guess.) Sorry to confuse all you would-be-matchmakers!
technically one isn't obligated to have tzitzis at all unless one is wearing a 4 cornered garment. today we go out of our way to have a four cornered garment to not miss out on the opportunity of a positive mitzvah. this being the case though once one starts taking on this as a regular action they may not stop doing so.