Shadrach, Meshach, and Abednego faithfully observed Jewish law and refused to worship King Nebuchadnezzar's god. The king was so angry he had them put into a fiery furnace to die a painful death.
However, when the king looked into the furnace, he saw a fourth man in the furnace who looked god-like, and no one was hurt. Because of Shadrach, Meshach, and Abednego's faithfulness, the king also began to worship the God of the Israelites. God protected and delivered his faithful servants. Do you trust God to look after you?
Jesus was encouraging some Jews who said that they believed in him, to stand firm in his word. In Jesus' word, they would find the truth, and they would be free. The Jews misunderstood what Jesus meant by being free. They said that since they were sons of Abraham, they had never been slaves - they seem to have forgotten about their slavery in Egypt.
However, Jesus explained that he was referring to slavery to sin. The truth that Jesus referred to is knowing God through Jesus and then following Jesus in doing God's will. That is the way to true freedom.
Lord Jesus, help me to draw close to God by following Your way.