This cement, sand, and water are like people before they become Christians. They are very different; but they can all be made into one solid piece of cement.
A few days ago I took some cement, sand, and water, and mixed them together in a cardboard carton, such as this one. I let the mixture harden, and it made this solid block of cement.
As I told you before, these three different substances are like unsaved people. They remind me of what Paul said in Galatians 3:28, "There is neither Jew nor Greek (Gentile), there is neither bond nor free, there is neither male nor female: for ye are all one in Christ Jesus."
The red cross on this carton speaks of Christ, and his sacrificial death on the cross for us. God's Word says that in Christ we are all one. All nationalities become one in Christ as they accept Him as Saviour, just as these three things—cement, sand, and water—become one solid block when mixed in the carton.
It is only as we are new creatures in Christ that we can really be one, and can obey Christ's command. "Thou shalt love thy neighbor as thyself."