The need for the practical expression of unity or oneness among saints in a city was a concern among the brethren as early as 1838, just ten years after they first began in Dublin. See details in Biography: G. V. Wigram: His Early History: London. However, as we will see, this understanding of one church in one city became a basis for centralizing believers into one meeting with all saints attending simultaneously.

The early practice of the Brethren related particularly to unity in administration. Leading brothers would fellowship together in the same city while all the other saints would be gathering in many homes, in many places, throughout the town or city. Practices such as the breaking of bread, preaching on the Lord's Day, week night prayer, and the public reading of the Scriptures, always took place in various parts of the city, sometimes called 'subdivisions' at the same time. Therefore, initially, the church in one city clearly had many gatherings simultaneously throughout the city as was practiced by believers in the first century.

In the ensuing years - and as traveling in larger cities became easier - the matter of one church in one city also found increasing expression in localized gatherings for edification by leading brothers. Over time, there were regular occasions for central or 'city' readings of the Scriptures on the Lord's Day, and week night 'city' readings and prophetic ministry meetings, as well as monthly care meetings, emulating "the whole assembly come together in one place." [1 Corinthians 14:23] It is possible that although formerly saints would gather house to house, the centralized meetings administered by the leading brothers, took precedence or even replaced the widespread gathering of the saints.

The expression of unity and oneness was not restricted to the meetings. Visiting one another and having company for dinner - especially on the Lord's Day - was an integral and vital part of life among the brethren. Saints displayed hospitality and welcomed one another into their homes as part of their church existence.

Lest there be any misunderstanding, I should clarify that use of the word 'assembly' does not imply any special status for the brethren - or pretension to alone be THE assembly - and does not exclude any of the saints who might gather otherwise or who are in the various 'churches'.