Initially the Missionaries had been founded as a society of priests to evangelize though preaching and sacraments. Two years later, when we became religious with vows, the element of religious life became an essential component of our vocation. This opened the door to men who wanted Oblate religious life without being priests. It was a problem for some of the priests whose focus was on clerical ministry which the brothers were unable to do. So why have them? Other Oblate priests were tempted to regard the brothers as domestic servants.
At one time didn’t you mention a candidate for the brothers? I passed on the news to the novitiate. I have sent Brother Ferrand to Corsica. That leaves us only Brother Roux. They are a rare breed but vital, and when they come to us it is important to give them a good formation.
Letter to Bruno Guigues, 3 May 1835, EO VIII n 514
So far I have only been able to send to Ajaccio Guibert, Telmon and Brother Ferrand, without whom Guibert tells me he wouldn’t have been able to open his seminary, so useful is he to them. Let’s have no more debate about the good brothers after that! So I’m going to admit Brother Roux to his final oblation. It’s up to the rest of you to come up with some more.
Letter to Bruno Guigues, 27 May 1835, EO VIII n 516
I refer you to “Our Founding Vision Today: All are Brothers, some are Priests” http://www.eugenedemazenod.net/?p=3155