A brief rundown on the stories:
William Tell is a Swiss legend about a famed man who was both an excellent seafarer and a dead shot with a crossbow. The story goes, a high-ranking official by the name of Gessler raised his hat in the town square and ordered all the peasants should bow to it. Tell - and his young son- refused. Gessler is to have them executed, but said he'd spare their lives if Tell managed to shoot an apple off the head of his son. He does. Gessler noticed he'd drawn two bolts and asks why. Tell confesses that if he'd missed, he'd have used the other to kill Gessler. Gessler is outraged, declares life imprisonment for Tell. But during a transport across a body of water, a storm strikes. The guards free Tell so he can steer them to safety, and he escapes.
Shadrach, Meshach and Abednego are from a Biblical story. In it, these three young Hebrew men are enslaved and living in Babylon. They grow both physically and in knowledge, as they're being trained to be in service of the Babylonian King, Nebuchadnezzar. During this time, Nebuchadnezzar erects a giant gold statue of himself and orders everyone to bow to it. Shadrach, Meshach and Abednego, being devout Jews, refuse. Nebuchadnezzar is filled with rage and has them thrown into a furnace that should burn them alive. However, they survive, and Nebuchadnezzar sees the error of his ways and lets them go.
The main point that stays consistent between them is that upon encountering a government official's display of vanity, both William Tell and Shadrach, Meshach and Abednego refused to bow down to it. Even when there were dire consequences - even when the consequence was death. Moreover, the stories make a point to say that these were skilled, educated men, and they ultimately escaped death. In the case of William Tell, it was his skill that saved him. In the case of Shadrach, Meshach and Abednego, it was their faith in God. In both cases, what defined their initial defiance (Tell's skill and dignity, Shadrach, Meshach and Abednego's unwavering faith) is the same thing that saved them.
