Mark 9:33-50
v33-37: Jesus knew what the disciples were arguing about, but He wanted them to own up and confess to Him their foolish words. He wants us to confess not just our sinful words, but our sinful thoughts and deeds as well. We are to do that remembering that He is the friend of sinners who is willing and able to offer forgiveness.
v38-41: "We tend to think that those who do not follow Christ with us are not following Christ at all, and that those who do not follow our ways are doing nothing well, but the Lord knows them that are his, however dispersed they are. This is a necessary warning to us to beware of being carried away by excessive zeal for the unity of the church, or for anything we are sure is right and good, with the result that we oppose what may lead to the enlargement of the church and the advancement of its true interests by another way… as long as those who differed in fellowship agreed to fight against Satan under the banner of Christ, they should look on one another as on the same side, despite the differences."
v42-50: Sin is to be put to death, killed, crucified, and starved. Temptation is to be kept away from. Idols are to be rejected. “Either sin must die, or we must die… If we are ruled by sin, we will inevitably be ruined by it."
Mark 10:1-16
v1-12: God Himself joined the husband and wife together. God "has not only, as Creator, fitted them to be comforts and suitable companions for each other, but also, in his wisdom and goodness, appointed those who are joined together in this way to live together in love until death separates them."
v13-16: Beware of discouraging anyone from coming to Christ.