"A holier relationship than one of blood"…

The faith which each man holds for the salvation of his own soul is a faith which joins him to every other believer. The close and mysterious union which is constituted by faith between him and his Saviour, is a union that connects him through that Saviour with every other Christian. In becoming one with Christ, he becomes at the same time, in a certain sense, one with all who are Christ’s. The spiritual fellowship that a believer enjoys with his Redeemer, is not a solitary or a selfish joy, but one which he cannot possess alone, or except in common with other believers. It is the very nature, therefore, of the Gospel to be not a solitary religion, but a social one. When Christ, through the Holy Spirit, brings a sinner into reconciliation and communion with Himself, He ushers him also into the fellowship of reconciliation and communion with all other Christians. When the work of grace is done upon the soul of man, and the barriers of separation between him and his Saviour are cast down, and the sinner who was afar off is brought near to God, the very same work of grace removes the obstacles that hindered his union with other men; and in the fellowship of one faith and one Lord he discovers a  new and mightier bond of attachment and union to his fellow-believers. Were there no positive command or appointment, therefore, requiring Christians to unite together and to form on earth a society joined together by the profession of the same faith, the very nature of Christianity would force such a result. In the profession of it in common, men would find themselves insensibly drawn to other believing men with a power not to be resisted; and in the bond of the same Saviour and the same Spirit they would feel and own a nearer tie than that of kindred, and a holier relationship than one of blood. In the common joys and sorrows which Christians, and none but Christians, share,–in the one faith and one Saviour in which together they rejoice,–in the same hopes and fears, the same sin escaped, and the same salvation won, in which they participate, there is a union of the most intimate kind produced and cemented, which is not with them a matter of choice, but a matter of inevitable necessity.

-James Bannerman, The Church of Christ: A Treatise on the Nature, Powers, Ordinances, Discipline and Government of the Christian Church (volume 1 PDF here, volume 2 PDF here)

The church is not an "accidental or voluntary union"…

When the Spirit works in an individual, He puts a love for his brothers and sisters in his heart (1 John 3:14; 1 Thess. 4:9). He will go where they are found. He will be where Jesus has set His own affections—on His Bride. He wants to be where God has raised up shepherds to lead and tend His flock, where God has given His sacraments to nourish His people and distinguish them from the world, where God has put His Word from which they will be fed. He wants to be with those who worship Jesus Christ. He wants to know the unity and love of the Spirit. He want to know and experience the support of other believers. He wants to be in and of the church.

But we are American consumers who have customized everything, even our faith. Our faith is our own and in so far as the church fits into our own individual faith, we will give it a place in our lives. Now, of course, God does deal with us as individuals. When we are converted, we have the right sense that God is dealing with our souls individually. That is certainly true, but after God converts a person, He provides him with a place to be nourished. The Father leads us to our Mother, the Church, where we will be nourished at her breast. Because our conversions were intensely individual matters and because of the evangelical Christian climate we live in, we have a tendency to think the whole of our Christian walk is an individual matters.

James Bannerman delivered a series of lectures called The Church of Christ (volume 1 PDF here, volume 2 PDF here), back in the middle 19th century. He wrote about this seeming struggle between individualism and the church:

Perhaps there are a few who confess Jesus Christ to be the Author and Finisher of their faith, who do not also confess, in one sense or other, that He is the Founder and Head of a society destined to embrace all His followers and fitted to be of permanent continuance. Men may differ widely as to their notions of the kind of community which Christ has actually established; but few, if any, will be found to deny that Christianity is designed to be something more than the religion of individuals, bound together by no tie, and gathered into no outward society.

Remember Bannerman is writing in 1869. That last statement he makes about few being found that deny that Christianity is “designed to be something more than the religion of individuals” is not true today. Many, if not most, assume Christianity is solely about a personal relationship to God without the church.

Bannerman continues…

In its primary and most important aspect, indeed, the revelation of God contained in the Bible is a revelation to me individually. Its discoveries of sin and announcements of judgment, its intimations of grace and its proclamations of a Savior, its offers of an atoning blood to expiate, and a regenerating Spirit to purge transgression,—these are addressed to me individually; and if I deal with them at all, I must deal with them as if there were no other in the world except myself and God. Alone with God, I must realize the Bible as if it were a message from Him to my solitary self, singled out and separated from other men, and feeling my own individual responsibility in receiving of rejecting it.

So, in other words, God does deal with us as individual souls. If you have not had that experience, that late-night all by yourself experience of God dealing with you and your sin, you may not be converted. That experience of conversion must be deeply personal—like the Apostle Paul on the road to Damascus. Ironically, the person who has not had that conversion experience may think that salvation consists in church attendance.

Bannerman goes on…

But the Bible does not stop here: it deals with man, not only as a solitary unit in his relation to God, but also as a member of a spiritual society, gathered together in the name of Jesus. It is not a mere system of doctrines to be believed and precepts to be observed by each individual Christian independently of others, and apart from others…

That last statement nails us. We believe Christianity in its entirety is believing certain precepts. And the thing about precepts is they don’t require any sort of society…just a brain. The man alone with his Bible is understood to be more mature in his faith than the sheep committed to the church.

It is not a mere system of doctrines to be believed and precepts to be observed by each individual Christian independently of others, and apart from others: it is a system of doctrines and precepts, designed and adapted for a society of Christians. This agreement and co-operation of men holding the same faith and the same Saviour is not an accidental or voluntary union which has grown up of itself: it is a union designed beforehand, appointed from the beginning by God, and plainly contemplated and required in every page of the New Testament Scriptures. There are precepts in the Bible addressed, not to believers separately, but to believers associated together into a corporate society; there are duties that are enjoined upon the body, and not upon the members of which it is composed; there are powers assigned to the community, to which the individuals of the community are strangers; there is a government, an order, a code of laws, a system of ordinances and officers described in the Scripture, which can apply to none other than a collective association of Christians. Without the existence of a Church, or of a body of believers, as contradistinguished from believers individually, very much of what is contained in the Bible would be unintelligible, and without practical application.

In other words, if you read your Bible, you will find that in order to be obedient to our heavenly Father, there is no getting around the church. To submit ourselves to the church is to obey the Father and allows us to fulfill all of those “one another” passages.