According to Britannica Kids, the simplest explanation of a prism is:
... a piece of glass or other see-through material that has several flat sides called faces. Prisms can be made in many forms and shapes. Light travels in the form of waves. Some light waves have long wavelengths while others have short wavelengths. Each wavelength produces a different color of light. Usually, all the wavelengths of light blend together to form light, but when light enters a prism, it bends. Light waves of different wavelengths bend by different amounts. The longest wavelengths bend the least. The shortest wavelengths bend the most. This bending separates the light waves so each color can be seen. This band of colors - red, orange, yellow, green, blue, indigo, and violet - is called a spectrum.

Jesus has called us to be the Light of the World.
Light not only brings out the beauty in the rest of creation, it exposes the rest of creation to the true light ... Jesus himself!
As disciples of the True Light, we each shine on different wavelengths, with different gifts and abilities. And those who are exposed to our shining will receive that light as uniquely as we deliver it.
So when we as believers shine our lights, we blend together so that those who so desperately need light exposure will have the opportunity - no matter where they are on the spectrum - to see the Light!
“You are the light of the world. ... let your light shine before others, that they may see your good deeds and glorify your Father in heaven" (Matthew 5:14-16, NIV).
"When Jesus spoke again to the people, he said, 'I am the light of the world. Whoever follows me will never walk in darkness, but will have the light of life'" (John 8:12, NIV).
Humans and birds aren't the only creatures that sing. Whales sing too. In fact, the songs of humpback whales are some of the most complex arrangements in the animal kingdom. Their ditties consist of vast roars, deep bellows, and groans interspersed with interesting sighs, chirps, whistles, and squawks.Their songs range from five to 30 minutes long.
Once a whale is done singing, it will surface to take a breath, then descend to about 50 feet, where it holds its position with its head down and then repeats the song verbatim, again and again, sometimes for hours on end.

As far as we know, only the males sing, and humpbacks in the same region of the ocean sing the same song. Each year, their songs change somewhat, as though they are experimenting with different arrangements.
The song of the humpback reaches sound levels up to 180 decibels — that's louder than a rocket blasting off! And researchers believe that some of these low-frequency sounds can travel more than 3,000 miles!
Did you know that the Bible says the loud voice of an angel can reach all around the world? "Then I saw another angel flying in the midst of heaven, having the everlasting gospel to preach to those who dwell on the earth to every nation, tribe, tongue, and people - saying with a loud voice, 'Fear God and give glory to Him, for the hour of His judgment has come; and worship Him who made heaven and earth, the sea and springs of water'" (Revelation 14:6, 7).
The Three Angels of Revelation 14 represent God's church of these last days. We, as members of His church are responsible for proclaiming the Good News of the Everlasting Gospel to the entire world. Like the mighty whales, we boldly proclaim, as the psalmist calls them, "songs of deliverance" to a needy world.
Sometimes the melodies will change, as we continually reassess how best to meet the current needs of our communities and our world. But the message will always be the same ... the Good News of the Gospel of Jesus Chirst, come "to seek and to save those who are lost" (Luke 19:10, NLT).
It's happens to all of us. We're walking along and suddenly become aware of a nagging little bump beneath the sole of our foot. Perhaps we're in a hurry and don't want to take the time to address it, so we try to ignore it. We're just too busy; it's not worth the effort.
Or perhaps we're not in an appropriate place or position to stop and remove our shoe to address the discomfort, so, again, we try to ignore it. We keep walking, trying to convince ourselves that it's fine, this is fine, no big deal.
But sure enough, there comes a time when we just can't ignore it any longer ... the shoe, and maybe even the sock or stocking, needs to come off so we can shake out the tiny pebble which made itself at home just beneath soft, tender pad of our foot.

Many (if not most) evangelical Christians get so nervous about witnessing to others. We fret not having all the answers, or feeling inadequate in presenting the "whole" of the Gospel message. So we shrink back and say nothing. But does this dichotomy of choices really exist? Or is there something in between?
Christian author, Greg Koukl, speaking to The Gospel Coalition, had this to say:
A wise ambassador ... weighs his opportunities and adopts an appropriate strategy for each occasion. ... Now here is my own more modest goal. I want to put a [pebble] in his shoe. All I want to do is give him something worth thinking about. I want him to hobble away on a nugget of truth he can’t simply ignore because it continues to poke at him.
Effective witness doesn't have to include a full, five point Gospel presentation. Sometimes all that's necessary is a little "nugget of truth" that nags at the unbeliever's conscience or phyche, until they simply cannot ignore it any longer. They have no choice but to "deal" with it, giving it greater consideration.
What they do with that nugget isn't our responsibility. It's entirely on them now. Will they simply remove it and toss it aside? Will they take it out and ponder how it got in there? Will it cause them to pause and consider further truth?
Remember, next time you feel intimiated to "present the Gospel" to an unbelieving relative, friend, or even stranger ... you don't have to drop a boulder on their head. You just need to drop a pebble in their shoe.
Matthew 13: 3-9 (NIV):
A farmer went out to sow his seed. 4 As he was scattering the seed, some fell along the path, and the birds came and ate it up. 5 Some fell on rocky places, where it did not have much soil. It sprang up quickly, because the soil was shallow. 6 But when the sun came up, the plants were scorched, and they withered because they had no root. 7 Other seed fell among thorns, which grew up and choked the plants. 8 Still other seed fell on good soil, where it produced a crop—a hundred, sixty or thirty times what was sown. 9 Whoever has ears, let them hear.