Object Lesson 9: "The Shepherd Knows His Flock"
Do not live your life to convince others, for only God knows your heart.
Many people spend their lives trying to convince others they are worthy of the kingdom of heaven. They may try to impress others by going to church each Sunday, giving lots of money to charity, and speaking no lies or dirty language. But this alone does not make them a Christian. It does not save, because we are not the judges. In this experiment, a series of optical illusions, specialized rubber balls, and a simple egg trick will demonstrate our inability to properly judge people, because we do not know their hearts. While we may look alike and even act alike, only Jesus really knows us. It is our personal relationship with Jesus that saves us, for the shepherd knows his flock.
Who is the judge?
What really saves?
“. . . The LORD does not look at the things man looks at. Man looks at the outward appearance, but the LORD looks at the heart.’” 1 Samuel 16:7
“My sheep listen to my voice; I know them, and they follow me. I give them eternal life, and they shall never perish; no one can snatch them out of my hand. My Father, who has given them to me, is greater than all; no one can snatch them out of my Father's hand. I and the Father are one.” John 10:27-30
Experiment 1: Optical Illusions (photos)
Internet – keyword ‘optical illusions’ or try this link
Colored cardboard sheets (optional: for framing out printed photos)
Experiment 2: Bounce / no bounce balls
Bounce / no-bounce balls – available at Steve Spangler Science
Experiment 3: Egg trick
Carton of eggs (1 dozen)
Experiment 1: Optical Illusions (photos)
Print color copies of optical illusions found on the internet. Paste them onto cardboard backings (optional). Set the optical illusions face-down on the presentation table.
Experiment 2: Bounce / no bounce balls
The bounce / no-bounce balls require no preparation. Just place them on the presentation table or keep them in your pocket.
Experiment 3: Egg trick
Boil one of the 12 eggs in the container for 10 minutes to hard boil the egg. Leave the other 11 eggs raw. Put all 12 eggs in the carton on the display table (there is no need to mark the hardboiled one, that is the trick).
1. “Hey kids.”
2. “Today we are going to talk about two important topics.”
3. “The first is on judging others.”
4. “The second is the importance of our personal relationship with Jesus Christ.”
5. “But first, let’s have some fun.”
6. “I have several pictures in front of me.”
7. “I will show them to you one at a time to see how well you can use your senses.” Show the photos one at a time.
8. “So, how well do you trust your senses?” Wait for a response.
9. “Your eyes are deceiving, aren’t they?”
10. “Let’s keep that in mind for now and move onto a story from the bible.”
Parable of the wheat and the weeds
11. “In Matthew 13:24-30 we read that the ‘kingdom of Heaven is like a man who sowed good seed in his field, but while people slept, his enemy came and sowed darnel (weeds) also among the wheat, and went away.’”
12. “But when the blade sprang up and brought forth fruit, then the darnel appeared also.”
13. “The servants of the householder came and said to him, ‘Sir, didn’t you sow good seed in your field? Where did this darnel come from?’”
14. "He said to them, ‘An enemy has done this.’”
15. "The servants asked him, ‘Do you want us to go and gather them up?’”
16. "But he said, ‘No, lest perhaps while you gather up the darnel, you root up the wheat with them.”
17. “Let both grow together until the harvest, and in the harvest time I will tell the reapers, ‘First, gather up the darnel, and bind them in bundles to burn them; but gather the wheat into my barn.’”
Explanation of the parable
18. “So, what does this mean?”
19. “Well, Matthew 13: 37-43 goes on to explain the parable.”
20. “Essentially, the field represents the world.”
21. “In this world, we find people who will be saved (the wheat) and those who will not be saved (the darnel or the weeds).”
22. “But, just as darnel and wheat look the same on the outside, so are the saved and the unsaved.”
23. “Only at the end will the wheat be separated from the weeds, the saved from the unsaved.”
24. “The weeds will then go into the furnace of fire while the righteous will shine forth like the sun in the kingdom of their Father.”
25. “Ok, so the moral of the story is that the world is full of non-Christians as well as Christians, but only the Christians will be saved.”
26. “But, do you think all people who claim to be “Christians” will go to the Kingdom of heaven?”
27. “Does simply saying you are a Christian make you go to heaven?” Wait for a response.
29. “Well, if it's not easy to see the difference between the saved and the unsaved, then how do you know whether other so-called ‘Christians’ around you are children of God?” Wait for a response.
30. “Oh, they go to church, give money to charity, and do not tell lies or swear.”
31. “So, do you think you can look the way a person talks and behaves and determine if they will be saved?” Wait for a response.
32. “Now, remember those optical illusions from before.”
33. “Do you really feel you are able to judge people fairly?” Wait for a response.
34. “Well, let’s see.”
Bounce / no-bounce balls
35. “Here I have two balls.” Show the bounce no bounce balls.
36. “Each appears to be the same.”
37. “Can you see any difference between these?” Wait for a response.
38. “No, they are both black.”
39. “They are both made of rubber.”
40. “So, what if I told you that one is just like the weed from the story?”
41. “It actually may do harm to the good plants, the wheat.”
42. “Are you sure you cannot see any difference between them? Wait for a response.
44. “They look the same.”
45. “But are they really the same?” Drop them at the same time.
46. “Wait, one bounced while the other did not.”
47. “What made one bounce and the other not?” Wait for a response.
48. “Oh, it was something on the inside that made the difference.”
49. “They are the same on the outside, but different on the inside.”
50. “In the bible we read in 1 Samuel 16:7 that ‘the LORD does not look at the things man looks at.”
51. “Man looks at the outward appearance, but the LORD looks at the heart.’”
52. “So, it is what is on the inside that matters, and that is only visible to God.”
53. “Let’s look at another example.”
54. “I have here a dozen eggs.”
55. “Only one egg is hardboiled.”
56. “The rest are raw.”
57. “Can you tell me which one is hardboiled?” Bring the carton of eggs into the audience and let them handle the eggs. Let a few kids think they have the right one.
58. “What if I said that after you choose, I will break it over your head?”
59. “How confident are you that you picked the right one?”
60. “Not so sure anymore, are you?” Wait for a response.
61. “Well, how can we tell them apart?”
62. “They are all the same color.” Show the audience the eggs.
63. “They are all the same size.” Show the audience the eggs.
64. “They are all the same weight.” Feel the weight of each egg.
65. “So, on the outside they are exactly the same.”
66. “But, what about the inside?”
67. “Remember, we read in 1 Samuel 16:7 that ‘the LORD does not look at the things man looks at.”
68. “Man looks at the outward appearance, but the LORD looks at the heart.’”
69. “So, is there a trick to look at the inside of an egg without breaking it?”
70. “How about by how they act?”
71. “Let’s spin the eggs and see how they behave.” One by one start to spin the eggs on their sides. Most will spin for a few rotations then stop. The hardboiled egg will spin longer. Once you identify the hardboiled egg, use that egg and one raw egg to show the kids side-by-side how they spin differently.
72. “See, it is the hard egg yolk and egg whites inside that made one egg spin longer than the other.”
73. “The more solid the inside, the longer it spins.”
74. “It is what is on the inside that matters, and with us, that is only visible to God.”
Can we judge?
75. “So, both the bouncing ball trick and the egg trick showed us that what appears to be the same on the outside can be quite different on the inside.”
76. “So, now that we have seen this, can we properly judge people?” Wait for a response.
77. “No, you cannot.”
78. “Only God knows their hearts.”
79. “So, if it's not easy to see the difference between the saved and the unsaved, then how do you know whether you are a child of God?” Wait for a response.
80. “Well, it has been said that the measure of a man’s character is best reflected by how he acts when no one is around.”
81. “The same is true of our faith in God.”
82. “It is our inner self, which is only known to God that determines our fate.”
83. “For it is our personal relationship with Jesus Christ, and not the one we show others, that saves.”
84. “So, what have we learned?”
85. “Well, unfortunately many people spend their lives trying to convince others they are worthy of the kingdom of heaven.”
86. “They may try to impress others by going to church each Sunday, giving lots of money to charity, and speaking no lies or dirty language, but this alone does not make him a Christian.”
87. “It does not save, because we are not the judges.”
88. “While we may look alike and even act alike, only Jesus really knows our hearts.”
89. “It is our personal relationship with Jesus that saves us, for the shepherd knows his flock.”
90. “Well, I better get back to the lab.”
91. “I have lots to do to prepare for my next experiment.”
92. “You see, I think I discovered a way to crush a soda can using nothing but air, as well as a way to make a ping-pong ball float in mid-air.”
93. “I just need to work the kinks out.”
94. “I will see you again soon.”
1. A great video showing several different types of optical illusions is available at http://www.youtube.com/watch?v=bOP37A1EhEs
2. Optical illusions are available at various websites. Here is one example: http://www.michaelbach.de/ot/index.html
3. Bounce no bounce balls are available for purchase at Steve Spangler Science (www.stevespangler.com). A video of bounce no bounce balls is also available: http://www.stevespanglerscience.com/experiment/00000094
4. A video of the egg trick as performed by Jenny Jones is available at: http://www.youtube.com/watch?v=HjRDYwk82h0. You can also check it out at http://www.youtube.com/watch?v=R6kDIdYCvjU
Please send comments, suggestions, and questions to Daniel at firstname.lastname@example.org
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