And they that went in, went in male and female of all flesh, as God had commanded him: and the LORD shut him in. -Genesis 7:16

See Noah and his family entering the ark! I do not think I should have selected the ark as a place of residence myself, nor would you have chosen to live in a place pitched within and without with pitch, with only one door and one window to it, and a great menagerie of birds, and beasts, and reptiles inside it. Whether that window ran all round the top just under the roof, so as to let light into the whole structure, I cannot tell; but I have no doubt that the jeering world said to Noah, “Well, old man, you have built a prison for yourself, and the sooner you go inside and shut yourself in the better; for we have had enough of your preaching!” When the good man and his family went in, and the Lord shut the door, they were dead to the world…When the Lord shuts you off from the world, you are best alone. Nowadays professors have not faith enough to dwell alone. They want two or three doors in the back of the ark, so that they may slip out every now and then, and do a little pleasuring with the world, and then glide back again and look like saints. As to being shut in with God and separated from the world-religious and irreligious-how few will endure it! How little is ever heard of that cry-“Come out from among them, and be ye separate!” “You might as well be dead,” cries one, “as be out of society.” Exactly so: and that is what the child of God looks for. “Ye are dead, and your life is hid with Christ in God.” “Buried with Him by baptism into death.” “God forbid that I should glory, save in the cross of our Lord Jesus Christ, by whom the world is crucified unto me, and I unto the world.” That separatedness which Noah took upon himself so willingly was involved in his salvation; for if he had lived with the world, he would have died with the world. Only in separation is salvation. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/2147.cfm

…being confident of this very thing, that He who has begun a good work in you will complete it until the day of Jesus Christ… -Philippians 1:6

If I look into the chambers of my inner nature, I see all manner of deficiencies and deformities, and I may well be filled with dismay; but when I see Christ there, my heart is comforted, for He will both destroy the works of the devil, and perfect that which He has begun in me. I am a sinner, but my heart rests on its Savior; I am burdened with this body of sin and death but behold my Savior is formed in me the hope of glory. I am by nature an heir of wrath, even as others, but I am born into the second Adam’s household, and therefore I am beloved of the Most High, and a joint-heir with Christ. Is there Christ in thy heart beloved? Then everything that is there that would make thee sorrow may also suggest to thee a topic for joy. The saint is grieved to think that he has sin to confess, but he is glad to think that he is enabled to confess sin. The saint is vexed that he should have so much infirmity, yet he glories in infirmity because the power of Christ doth rest upon him. He is grieved day by day to observe his wanderings, but he is also rejoiced to see how the Good Shepherd follows him and restores his soul. So that all the evils and short comings in me which make me weep, also make me glad when Jesus is seen within. For all I see within myself lacking or sinful, I see a sufficient remedy in Christ who is all in all.

Christ is not only all by way of distinction, but He is all to God, all between us and our enemies, and all within ourselves. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/1006.cfm

For there is one God and one Mediator between God and men, the Man Christ Jesus – 1 Timothy 2:5

Happy art thou, O child of God, that in all thy relationships to the Great Judge of all the earth, Christ is all in all to thee. Thou needest a mediator to stand between thee and God; Christ is that. Thou wantest a high Priest to present with His own sacrifice thy prayers and praises; Christ is that. Thou wantest a representative to stand at all times before God, an intercessor to plead for thee, one who shall be a daysman akin to thee and akin to God, who can put His hand upon both; Christ is that to thee. Whenever God looks upon thee in Christ, He sees in thee all that ought to be there… “Who shall lay anything to the charge of God’s elect? It is God that justifieth.” Without spot, or wrinkle, or any such thing, is the entire church as seen in the person of Christ Jesus, her representative and head. Christ is all for us before the throne of God.

But, alas! we need some one to stand between us and our enemies. There is Satan; how shall I meet him? He will accuse me; Who shall plead my case? Christ is all in all for that. Whatever fiery darts Satan may shoot, Christ is the shield that can quench those darts. If Satan tempt me, Christ shall plead for me before the temptation comes. Whenever I have to contend with Satan, this is the weapon with which I should arm myself: If I reason with him, if I bring forward any strength of my own to oppose him, he may well say to me: “Jesus I know; but who art thou?” But if I bring Jesus into the conflict, and wield the merit of His blood, and the faithfulness of His promise, the destroying angel cannot overcome the sprinkled blood. We overcome through the blood of the Lamb. Christ Jesus is both shield and sword to us, armor and weapons of war. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/1006.cfm

And let the peace of God rule in your hearts, to the which also ye are called in one body; and be ye thankful. – Colossians 3:15

The Greek said, “The Hellenes are a race of heroes; remember Sparta and Athens. Are we not foremost in civilisation, and were we not chief in war? Who set bounds to the Persian tyrant, and bade the boastful monarch bite the dust? We hold our heads erect when we think of Marathon and Salamis.” But when the Greek joined the Christian church, he forgot his national boastings, and henceforth gloried only in the cross of Him whose single arm defeated the hosts of Satan, and led captivity captive. The Jew when despised returned scorn for scorn, and said to Greek and Roman, “You may speak of Marathon, but I sing of the Red Sea; you may boast of Persia broken, but I tell of Egypt vanquished, mine are the glories of the Lord of hosts in the far off ages. We were a people when you were as yet unknown, and we are the chosen favourites of Jehovah.” The moment the Jew sat down at the gospel supper, he laid aside his hereditary pride and bigotry, and recognised the fact that the Greek was as much a brother as the believing Hebrew at his side. So the Sythian, when he came into the Christian church, was no longer a Barbarian; he spoke the language of Canaan as correctly as his Grecian fellow Christian. The slave no sooner breathed the air of the Christian church than his shackles fell from him. He might be a slave at home with his master, but he was no slave there. While the freeman, though he had been born free, or with a great price had obtained his freedom, never in the Christian church looked down upon the slave. Bond and free were one in Christ Jesus. Nobody had any personal ground for glory; neither race, nor pedigree, nor rank, nor position, were of any account, but Christ was all. “Christianus sum, I am a Christian,” was and is the universal glorying of all saints.~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/1006.cfm

Where there is neither Greek nor Jew, circumcision nor uncircumcision, Barbarian, Scythian, bond nor free… – Colossians 3:11

Observe, “there is neither Greek nor Jew, circumcision nor uncircumcision, barbarian, Scythian, bond nor free,” in the new creation, but “Christ is all, and in all.” In the new world there is no difference between Jew and Gentile; Barbarian simplicity and Greek cultivation are as nothing. I suppose as long as we are in the flesh we shall set some store by our nationality, and like Paul shall somewhat glory that we were free born: but surely the less of this the better. Within the gates of the Christian church we are cosmopolitan, or rather we are citizens of the New Jerusalem only. As a man, I rejoice that I am an Englishman, but not with the same holy joy which fills me when I remember that I am a Christian. When I meet another man who fears God, I do not want him to think me an Englishman, nor do I desire to regard him as an American, a Frenchman, or a Dutchman; for we are no longer strangers and foreigners but fellow-citizens. If any man be a Christian and a foreigner after the flesh, he is yet in spirit ten thousand times more allied to me than if he were an Englishman and an unbeliever. Greatly is it to be deplored whenever the convulsions of nations drag Christian men into opposition to one another on the ground of politics. One part of the body of Christ cannot be at war with another. It is a shameful thing whenever we suffer our earthly nationality to dominate over our heavenly citizenship. Queen Victoria and President Grant are well enough in their places, but King Jesus is Lord of all; we are above all things subjects of His Imperial Highness, the Prince of Peace. Nobody comes into the church as a Jew or a Gentile, nor does he remain there as a Greek or a Scythian, whatever he may have been before; when he becomes a Christian, Christ is all. Earthly distinctions of rank, if they still exist, as they must while we are in this world, are brought to a minimum within the church, they are almost obliterated, and what remains is sanctified to sacred ends.~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/1006.cfm