• What's a Nazirite vow?
  See Numbers 6:1-21.  In a nutshell, it is a voluntary vow that a man or woman can take to be consecrated to God for a period of time.  The consecration consists of not drinking wine or any food or drink made from grapes, not cutting your hair (note: actually the beard is not included; compare Numbers 6:18 with Leviticus 14:9), and not becoming ceremonially unclean by touching a dead body.
• Isn't it an Old Testament thing?
  No.  It's a Jewish thing.  Paul took a Nazirite vow (Acts 18:18), and Paul also paid for the sacrifices so that three Jewish believers in Jesus could complete their Nazirite vows in Jerusalem (Acts 21:23-24).  (Sidenote: if you think that Paul was compromising his belief in justification by faith by doing this, go back and read Acts 15.  For Jewish believers in Jesus, keeping the law is about voluntary obedience and love for God.  According to Hebrews 7:11-19, no one was ever saved by keeping the Law.)
• But you're not Jewish...
  No.  That's true.  However, I do love Jesus and I have a desire to be consecrated to Him.  In a sense, I borrowed a Jewish act of consecration because contemporary American evangelical culture does not have any comparable means of sacrificially expressing devotion to Jesus.  And it is in the Bible after all...
  
• Did Lou Engle dig this up on his own?
  Lou Engle apparently had a dream in the late '90s about calling out contemporary Nazirites as a challenge for 21st century America.  But he's not the first one to go back to the Old Testament and find this vow.  As at least one example, Rees Howells performed a Nazirite vow in the early 20th century (see Rees Howells: Intercessor, by Norman Grubb, pages 113-120).
• What's the point?
  The Bible actually says basically nothing about what the vow is for.  I'll post some more thoughts below, but one thing that I do want to say very clearly is that a Nazirite vow does not earn favor with God.  We are accepted by God only and entirely because of what Jesus did at the Cross.  If we are in Christ, God enjoys us as His children and delights in us because of our sincerity of heart - that is, our pursuit of complete obedience (pursuit, not the attainment of it).  No act of devotion can make Him love us more, just as no sin can make Him love us less.  On the flip side, if we are living in unrepentant sin, no act of devotion can make up for the lack of obedience either ("To obey is better than sacrifice", 1 Samuel 15:22).

What I Learned

My Nazirite vow began on January 21, and lasted for 208 days, ending yesterday.  Reflecting back on the past 200 days (as I rub my shaved head), the following thoughts come to mind:

• I am weak but He is strong.
  The deepest insight that I have gained out of this experience is my weakness.  If I thought I was out to demonstrate my holiness by a act of radical devotion, I failed completely.  For much of this time, I have been half-hearted in prayer and pursuing intimacy with the Lord.  I fell into all the same sins I struggled with before.  And therefore I felt like a hypocrite - I had the symbol of my consecration on my head, but I wasn't living a consecrated life. 
  
  In the end, I have come back again at a deeper level to the place where I started.  If my hope of living the Christian life depends on  me, I'm screwed.  I am weak.  Though I still hope and pray for breakthroughs and increasing victory over specific areas of sin, I will always be weak.
  
  But He is strong.  My hope is not in my faithfulness, my ability to obey His commandments consistently, my ability to fast, or my perseverance in prayer.  My hope is in Him - Him alone!
  
  Lamentations 3:22-24
  ²² Through the Lord’s mercies we are not consumed,
  Because His compassions fail not.
  ²³ They are new every morning;
  Great is Your faithfulness.
  ²⁴ “The Lord is my portion,” says my soul,
  “Therefore I hope in Him!”
  
  
• Being a Walking Declaration of the Worthy God
  Something I've thought about a lot is why God set up the Nazirite vow the way that He did.  The Nazirite vow might seem to be similar to fasting as an expression of "radical" devotion to God in the contemporary Church, but there are major differences. 
  • Fasting has a very practical dimension - it weakens your body, not just as a symbol of dependence on God, but as a means of actually increasing conscious dependence on God.  The Nazirite vow is basically symbolic. 
  • Fasting is to be primarily a private practice (Matthew 6:16-18), but the Nazirite vow is impossible to hide.
  • Fasting was mandatory for the people of God in the Old Testament (Leviticus 23:26-29), and is expected in the New Testament (Matthew 6:16, 9:15). The Nazirite vow, with the exception of a few special cases (e.g. Samson, Judges 13:5), is voluntary.
  • Fasting includes a dimension of seeking (seeking an answer to prayer, e.g. David, 2 Samuel 12:16; or seeking revelation, e.g. Daniel, Daniel 10:2-3, 10:12).  The Nazirite vow is more often an expression of gratitude and overflow towards God (e.g. Samuel, 1 Samuel 1:11).
  So what is the Nazirite vow really about?  I have two Biblical observations:  First, the Nazirite vow in the beginning of Numbers 6 immediately precedes the Aaronic blessing (Numbers 6:22-27).  Second, Nazirites are mentioned in the same breath with prophets in Amos 2:11-12.
  I think that the fundamental purpose of a Nazirite vow - a very public, strange, symbolic, and voluntary expression of devotion to God - is to serve as a walking declaration of the existence and beauty of God.  The Nazirite becomes a public reminder of God as he or she lives out life.  If the culture is walking in awareness of and obedience to God, then the public reminder is a blessing and the Nazirites contribute to the blessing of the society.  But if the culture is in rebellion against God, then the Nazirites are an ever-present rebuke to the godless self-seeking that surrounds them.  That is why the people of Israel in Amos' day suppressed the Nazirites.
  I am reminded of something I experienced when I spent a weekend at a Benedictine monastery a few years ago.  The monks' way of life - their silence, their Latin prayers, their old-fashioned cloaks and sandals, and above all the awareness that they would do this for the rest of their lives - were all very foreign to a 21st century American.  The overwhelming feeling I had, however,  was that Jesus is worth it.  He is worthy of that kind of odd, irrelevant, radical devotion - and so much more!
• Grapes are in everything!
  I expected the hair part of the Nazirite vow to be challenging, but I didn't expect the grapes part to be so bad.  It turned out that not eating grapes was far more troublesome than having of long hair and a beard.
  
  One issue that every Christian Nazirite needs to face immediately is the question of communion.  I decided that I would take communion, since I normally commune even when I'm fasting, and I thought of it as roughly parallel.  So I drank grape juice whenever I had communion.
  
  Much trickier is the issue of vinegar.  Vinegar - often, but not always, made from grapes - is in all kinds of things, from hot sauce to salad dressing to Wonderbread (Wonderbread??).  I decided early on that I wasn't going to bother with avoiding vinegar (actually, I decided retroactively after about three weeks of having eaten hot sauce practically daily...).
  
  Even without the vinegar, though, it is still hard to avoid grapes completely.  It turns out that grape juice (usually white grape juice) is the favorite mixer juice for most of what you buy in the store.  So if you buy any kind of juice product that isn't 100% some other kind of juice, it's very likely that it has grapes in it.  Crazier yet, I found a few different kinds of bread that had raisin juice extract in them.  It wasn't raisin bread.  It was just plain whole wheat bread.  But for some reason, they felt that it needed raisin juice.  So I ended up checking ingredients on almost everything I bought.
  
  
• Hair doesn't burn very well.
  At the end of the Nazirite vow, you're supposed to shave your head and take the hair to the Temple and burn it on the altar.  Obviously, there's no Temple now, but I did decide to burn the hair that I shaved off.  It was an interesting experience.  It turns out that in order to burn hair, you really need a pretty good fire that is already burning something else.  Hair itself doesn't so much burn as melt.  Not having any lighter fluid, I ended up spraying it with WD40 to get it to burn, and even then, it took a while.
  
  It was actually a neat insight with which to end the vow.  I don't know if you would see the same thing if you actually threw your hair onto an altar fire and watched it burn up, but I found that in trying to burn my hair I gained an appreciation for how God designed it.  Once hair catches fire, it melts and chars into a plastic-looking ash, and then it goes out.  If the hair is packed together, that only happens to the outer layer.  The inside isn't burnt.  So if your hair actually caught on fire, the likelihood of your head getting burnt would actually be pretty low.  God gave us a semi-flame retardant covering for our heads!