Are there any halachos pertaining to a mans hair length? how short it must be? are there sources for this? thank you.
Answer: There are no formal halachos concerning how short a man’s hair should be. However, the following three ideas should be born in mind.
1) Tefillin. Long hair, in particular when the hair is so long that hair from the front of the head is brushed to the back of the head, can involve an issue of chatzitzah — a “partition” between the tefillin and the head. See Peri Megadim to Shulchan Aruch, Orach Chaim 27:4 (and see also Machatzis ha-Shekel).
2) Lo Silbash. It is generally the way of women to grow hair long, and not the way of men. However, there is room to argue that this depends on style, and that even longer hair can be the “way of men.”
3) Be-Chukoseihem lo teleichu. Growing long hair displays a cultural affinity with non-Jewish culture, and should therefore be avoided. Even if there is no formal prohibition involved, this will at least be an issue of chinuch.
For these reasons, hair should be kept to a reasonably short length.
1) See Zevachim 19a, Erchin 3a, Beis yosef 27, Shulchan Aruch 27:4, Magen Avraham 4, Machatzis Ha-Shekel and Peri Megadim.
2) See Nazir 58b, Rambam, Idolatry 12:9-10; Shulchan Aruch, Yoreh De’ah 182, Gilyon Maharsha 6.
3) See Rambam, Idolatry 11:1-2, Kessef Mishnah, Maharik 88, Shulchan Aruch, Yoreh De’ah 178, Biur Ha-Gra 7.