Negative Commandment #184
Sefer Ha’mitzvos Ha’Katzar (The concise book of mitzvos)
By the Chofetz Chaim
This book lists the Torah mitzvos that can be observed today
Second Section – the Negative Commandments
184. It is a negative commandment "do not transgress a vow"
As it states in Bamidbar (Numbers) 30:3, "A man who takes a vow... he shall not break his word." (see Positive Commandment #39)
This applies in all places and all times, for men and for women.