Here's a simple "science" experiment that has 2 different "effects" demonstrated in it that are also fun magic tricks too. The first trick shows the arrow sign "reversing" because of the refraction of the water when it is poured into the bottle. The second trick shows a packet of ketchup "magically" rising and falling due to pressure being applied to the bottle of water.

Use it to stimulate a discussion about "what it means to obey" and "why we have rules."

Some quotes from the video:

• Why do we have all these crazy rules?
• Because I love you.
  
• If you don't follow the rules, you may end up getting punished*.
  
• The Bible/God explains how he wants us to live because he cares about us.
  
• When we obey God, he blesses us**.
  
• How do we make good choices?
  
• If we follow Jesus, the Holy Spirit lives inside us and helps us to make good (unselfish choices)

See my endnotes for important explanations of "punished" and "blesses us" especially as they relate to the Parable of the Prodigal Son, but also as they related to the concept of "obedience" in general!

See the demonstration...

Luke 11:28  “Blessed rather are those who hear the word of God and obey it.”

*"punished"

You'll definitely want to parse this with your kids. Some Christians believe God actively punishes us for disobedience -- makes life harder, sends plagues, etc. And to be sure, there are some verses in the Bible that suggest this.  However, some Christians (like myself) go with Jesus on this matter when he said in Matthew 7:9-11, "What father if his child asked for bread would give them a stone?"  (This isn't the first time Jesus has corrected traditional thinking!)

It's our own bad choices and life itself that punish us with consequences. Our emotions and conscience, for example, make us feel bad, guilty, ashamed when we do wrong. If we are unloving or selfish, people won't want to be around us. If you disobey stop signs, you'll eventually get hurt.

Look closely at the Parable of the Prodigal Son and you will see Jesus' opinion that our Father's love is unconditional and always ready to forgive. The father doesn't punish he son or even lecture him. He simply welcomes him home and celebrates. The consequences of the prodigal's disobedience led him both to ruin and onto his knees in confession.  (FYI: Jesus dispelled the old idea that our mortal condition (disabilities, leprosy, etc.) were God's punishment on the wicked. Instead, he touched and healed.)

**"he blesses us"

There's an awful theology infecting some churches called the "Prosperity Gospel." It's the idea that if you "do good, God will give you things." It's a perverted way of thinking about "why" a person should do good. By contrast, Jesus preached the Gospel of Love, which is sacrificial, not expectations, motivated by love, not rewards.

A Christian does not ask "what's in it for me?" Paul put it this way in 1 Cor 13:5.   "(love) is not self-seeking." The younger brother led a self-seeking life and it blew up in his face. The older brother had, as his father put it, "everything" except the one thing that he truly needed, a forgiving heart.

The ring, robe, and sandals he gave the younger son in the Prodigal parable, were not "gifts for being good" but signs of restoration. The robe and sandals signified he was clean in the father's eyes, not covered in unclean pig slop (sin). The ring signified he was his father's son, part of the family. The younger son NO LONGER expected these things, and didn't ask for them!  In fact, had the younger son asked for them, he would have been just like the older brother who was left standing outside the party at the end of the parable wondering "where's mine!!?" There is no greater blessing than knowing you have the love of the Father, are always welcome in his house, and will have the love and support of those who know it isn't right to cast stones (and know Jesus doesn't either).