Numbers 6:5

No razor shall come upon his head Nor scissors, or other instrument, to cut off any part of his hair. This is the second rule he was to observe, and appointed, partly as a sign of his mortification to worldly delights and outward beauty; partly as a testimony of that purity which he professed, because the cutting off the hair was a sign of uncleanness, as appears from Numbers 6:9; partly that by the length of his hair he might be constantly put in mind of his vow. Holy That is, wholly consecrated to God and his service, whereby is shown that inward holiness was the great thing which God required and valued in these, and consequently in other rites and ceremonies.