Numbers 6

"When either a man or woman consecrates an offering to take the vow of a Nazirite, to separate himself to the Lord, 3 he shall separate himself from wine and similar drink; he shall drink neither vinegar made from wine nor vinegar made from similar drink; neither shall he drink any grape juice, nor eat fresh grapes or raisins." vv.2-3

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Who's the first person in scripture you think of when you read this chapter about the Nazarite vow?  Samson right?  "And the Angel of the Lord appeared to the woman and said to her, “Indeed now, you are barren and have borne no children, but you shall conceive and bear a son.  Now therefore, please be careful not to drink wine or similar drink, and not to eat anything unclean.  For behold, you shall conceive and bear a son. And no razor shall come upon his head, for the child shall be a Nazirite to God from the womb" (Judges 13:4-5).
We see the Nazarite vow in two forms in scripture, 1) all a persons life, i.e. Samson, Samuel, John the Baptist; 2) those who took a vow for a certain amount of time, i.e. Paul, this was the general use of the vow.  Any man or woman could take this vow.  The vow would be a special volunteer duty unto the Lord that would make him or her set apart.  The Hebrew word is NAZIR which means 'set apart.'  There would be certain restrictions like not eating or drinking anything from the grape vine, not going near a dead body, not cut their hair.  When the vow was over there was to be a sacrificial offering.
If we make a vow to the Lord today we don't need to carry out the Nazarite regulations, but we can learn from it to set ourselves apart from others to practices discipline of denying  and be spiritually minded.  Be careful in making a vow for Ecclesiastes says, "When you make a vow to God, do not delay to pay it; For He has no pleasure in fools.  Pay what you have vowed—Better not to vow than to vow and not pay."  What is a vow you have made unto the Lord?