And Jesus answered and said unto her, Martha, Martha, thou art careful and troubled about many things: but one thing is needful: and Mary hath chosen that good part, which shall not be taken away from her. Luke 10:41,42

There is great talk now-a-days of union; the walls of the various churches are to be broken down, and the denominations are to be blended. Think not of it in such a fashion; the only union possible, or desirable, is that we all unite to sit at Jesus’ feet. It is not allowable that we concede one truth and you another; that is not natural charity, but common treason to Christ. We have no right to yield an atom of the truth of God, under the pretence of charity. Truth is no property of ours; we are only God’s stewards, and it behooves us to be faithful to our trust. Neither one church nor another has any right to bate its testimony one jot, if it be true. To alter the statute-book of Christ is blasphemy. True union will come when all the churches learn of Christ, for Christ does not teach two things opposed to each other. There are not two baptisms in the Bible; we shall not find two sets of dogmas diametrically opposite to each other. If we give up the various things that are of man, and hold fast each of us only that which is of God, we shall be united in principle and in doctrine; and “One Lord, one faith, one baptism” will once again be emblazoned upon the banners of the church of God. Sit at Jesus’ feet, O thou church of Christ, and true unity will come to thee.

We hear a great deal about the necessity of controversy. We ought to be ready to answer all that infidels object, so wise men say. Every absurdity of every fool we are to sit down and reply to, and when this labour of Hercules is accomplished, we are to begin again, for by that time new whimsies will be in men’s brains, and new lies will have been begotten. Is this so? Am I to do nothing in winning souls and glorifying God, but to spend all my time in finding wind for the nostrils of the wild asses of the desert? Well, let those do it who please, we believe that the settlement of all controversy in the church and for the church would come from the Lord Himself, if we believed more fully in Him, and waited more upon Him for guidance, and if we preached the gospel more in His own strength, and in His own Spirit. ~ C.H. Spurgeon

https://www.blueletterbible.org/comm/spurgeon_charles/sermons/1015.cfm