Who do you say Jesus is? A good man, somebody who had the word of God who made it possible for you to be saved, or the savior who saved you? And how do you view the cross, both Christ's cross and the crosses he allows in your life? Are they something that aren't glorious to you, or do you see God's glory through them?
Jesus has done everything well. He heals a man of deafness so that he could hear and believe the good news of salvation in Christ. Jesus has also opened your ears to hear his Word and believe it. Jesus heals the man so that he can speak. Jesus has given you faith so that you can pray to God on behalf of your friends and share the good news of salvation with them.
When comparing natural religion to God's religion, we see that natural religion simplifies sin (like "cooties") when our sinful nature is in fact a mortal disease that only God can cure. Natural religion also follows human traditions instead of using God's word without modification. Finally, natural religion focuses on the external consequences of sin instead of the internal new man we have been given.
When you want to ask God why he is allowing your pain and suffering, trust that he is planning and doing much more than you can understand. Trust that he has made and rules the universe for your eternal good as proven by the fact that he has saved you.
Johnathan and David were true friends and they showed unfailing kindness to each other as God gave them the opportunity. In this sermon we see that friendship shows unfailing kindness and that means being willing to speak up when a friend is in mortal peril. That means being willing to warn them of the mortal disease that all people have, which is called original sin. After warning them, we have the joy of showing them their Savior, who is the best friend of all sinners. We also get to show them how Jesus is ruling every day in their lives.
The Sabbath rejuvenates us with true worship, not the worship of our sinful nature or the ways of this world. That means God is rejuvenating us with his Word which assures us of our forgiveness and our salvation. It also rejuvenates our toils with a joyful harvest.