The amazing thing that I just discovered in reflection on thses verses is that these parables about the lost sheep have different meanings in each of these contexts. When I saw this I said “whoohaaa!” It was a revelation I had not thought about before. The Matthew passage was designed to show the care God takes for the preservation of the saints, as a reason why we should offend them. The Luke passage on the other had is designed to show the pleasure that God takes in the conversion of sinners, as well as to give us a reason we also should rejoice in a sinner’s conversion by faith and repentance.
In Matthew, Jesus begins this teaching to his disciples with a rhetorical question, “What do you think?” to redirect their attention from their contest to be the greatest in the Kingdom (Matthew 18:1), to being more concern about not offending little ones, lambs of Christ’s flock. Similarly, in Luke, Jesus starts with a question (but this time to the Pharisees), “What man of you…?” to correct their attitudes toward sinners. Our attitudes should not be so prideful as to think more about our place in the kingdom or how much better we are, than to look out for little children or lost sinners of the sheepfold. There is great spiritual danger and possible judgment on those, that because of their arrogance, who hurt one of the little ones and don’t have passion for seeking the lost sheep. The lost little children and lost sinners who don’t seem to have much value are of value to God in his redemptive plan. God is seeking lost sheep! God’s passion is to find lost sheep, and will not quit until he does this successfully.