Is your hair long? Let us plug these verses back into context.
6 And the Lord spoke to Moses, saying,
2 “Speak to the people of Israel and say to them, When either a man or a woman makes a special vow, the vow of a
Nazirite, to separate himself to the Lord,
3 he shall separate himself from wine and strong drink. He shall drink no vinegar made from wine or strong drink and shall not drink any juice of grapes or eat grapes, fresh or dried.
4 All the days of his separation he shall eat nothing that is produced by the grapevine, not even the seeds or the skins.
5 “All the days of his vow of separation, no razor shall touch his head. Until the time is completed for which he separates himself to the Lord, he shall be holy. He shall let the locks of hair of his head grow long.
These are but some of the conditions of taking the vow of a Nazirite which is a temporary vow and I would add one that cannot be done any longer because the sacrificial system has been fulfilled in Christ.
The Holy Bible: English Standard Version (Nu 6:1–5). (2016). Crossway Bibles.