A reason that I propose for why divorced women continue to cover their hair and divorced men continue to wear a tallis (a phenomenon whose existence I vouch for) is that taking on a mitzvah (with the intention to keep it going) is seen as making a vow(1), and so we do not roll back that action. In general, it seems there is a Jewish philosophy that observance may be increased, but never decreased(2).
In modesty this reason is obvious to me: something that becomes ervah cannot later become not-ervah. So we do not roll back our increases in modesty in particular.
My question is this: if a woman becomes a baalat teshuva after being divorced, must she cover her hair (as she never did before)? If a man becomes a baal teshuva after being divorced, must he wear a tallis (as he never did before)? If so, how does that square with my assumptions above?
(1) Source: A text I have seen used by some for Hataras Nedarim on Erev Rosh Hashana includes as a vow to be annulled:
"...אוֹ אֵיזֶה דָבָר טוֹב שֶׁנָהַגְתִּי שָׁלשׁ פְּעָמִים וְלֹא הִתְנֵיתִי שֶׁיְהֵא בְּלִי נֶדֶר..."
I posit that this applies even to obligatory acts.
As my source, consider these quotations of text:
"The Talmud in Tractate Shabbat relates that the academy of Hillel advocates lighting the candles as we know today, in ascending order. The academy of Shamai disagreed and argued that we light the Chanukah candles starting with eight candles on the first night, then seven candles on the second night. This method continues in descending order, so each night has one less candle than the preceding night. “Each viewpoint has either a model from the Torah or a logical argument to support their opinion.” Beit Hillel applies “a general rule that is followed in many areas of Torah: “One increases in matters of holiness, and does not diminish” “Maalin Ba’Kodesh ve’ayn Moridin.”
Halacha follows Beit Hillel, and this is why we light increased candles every day.