A white tallith and a tallith with black stripes
Question
My father always used to buy a tallith (prayer shawl) that was completely white, because this is the preferred way of performing the commandment according to kabbala. But now my father-in-law bought me a tallith with black stripes. If I won’t wear it, my father-in-law and my wife will be very upset at me. Is there a problem?
Answer
It is definitely better to wear a tallith with black stripes than to upset your father-in-law and to cause friction within your own family, G-d forbid. But it would be a good idea for you to do an annulment of vows; you should say that had you known that your father-in-law would buy you this kind of a tallith, you would state clearly that wearing a tallith that is completely white is without accepting it as a vow (“bli neder”).
Source
Shulchan Oruch, section Orach Chaim, ch. 9, §5; Chido, Shiyurei Brachah, subsection 2