A wall separates rooms; but it also keeps people from having fellowship with each other. In the Old Testament dispensation the walls of Jerusalem separated the Israelites from unbelieving Gentiles who came up against them, or tried to sell goods in the city on the Sabbath day.
Now, however, in the wonder of God's grace, members of the body of Christ are gathered out of every nation, tongue, and tribe. That is why Paul writes in Ephesians 2:14 , "For he is our peace, who hath made both one, and hath broken down the middle wall of partition between us."
Here we see why in Isaiah 9:6 Christ is called the Prince of Peace. He realized by His cross peace for us with God. But also on the day of Pentecost the apostles were enabled to speak with the people of other tongues, in their languages, because those hearers also were going to be gathered as members of the church.
There was a wall between Abraham's seed and the Gentiles, even as God told the devil that there would be two seeds in this world from the day of man's fall into sin. From Abraham's day onward God gathered His people almost exclusively from Abraham's seed. And still today there is the church and the world, the believers and unbelievers.
But in the wonder of God's grace the Prince of Peace came, and now we who are not Israelites physically, are not of the seed of Abraham, we also are being brought into the church of God and given faith, hope, and love.
Today the church is being gathered out of all nations. There are saints of every color and race saved by grace and included in the body of Christ ¾ His body having different kinds of members even as ours do. And we, saved from sin, will also be saved from separation between believers of other nations and races. Christ, the Prince of Peace, will realize a wonderful peace when He returns with glorified bodies for us.
Read: Revelation 5 .
It is shocking to think how persons dare to remain members of Christian churches, and even to enter the pulpit, when they are conscious that their private life is foul. Oh, how can they do it? How is it that their hearts have grown so hard? What! hath the devil bewitched them? Hath he turned them away from being men, and made them as devilish as himself, that they should dare to pray in public, and to sit at the sacramental table, and to administer ordinances, while their hands are foul, and their hearts unclean, and their lives are full of sin? I charge you, if there are any of you whose lives are not consistent, give up your profession, or else make your lives what they should be. May the eternal Spirit, who still winnows his Church, blow away the chaff, and heave only the good golden wheat upon the floor! And if you know yourselves to be living in any sin, may God help you to mourn over it, to loathe it, to go to Christ about it to-night; to take hold of him, to wash his feet with your tears, to repent unfeignedly, and then to begin anew in his strength, a life which shall be such as becometh the gospel.
C. Spurgeon on Philippians 1:27