For starters I am an atheist.
You are not translating that line well. Assuming you are trying to make all the various parts of the bible fit together its pretty clear you should cut your hair but not your beard.
Ezekiel 44:20
They shall not shave their heads or let their locks grow long; they shall surely trim the hair of their heads.
Leviticus 19:27
You shall not round off the hair on your temples or mar the edges of your beard. (this is about side burns and beards)
1 Corinthians 11:14
Does not nature itself teach you that if a man wears long hair it is a disgrace for him,