The order sought to "listen and teach" in order to understand God. In the 23rd century, they came to realize that understanding the religions of the many species in the universe would better help them to do that, as God was likely present and was part of all those religions in some way. Instead of visiting all their homeworlds, which could take centuries, the order realized that they could do what they needed on Babylon 5 where many races congregated. The Order arrived on Babylon 5 in 2260 led by Brother Theo Ankises and their permanent resident status was approved by Susan Ivanova.
While it is not clear if any of the other monks are ordained, Brother Theo clearly is shown dispensing the sacraments of Anointing of the Sick and the Holy Eucharist.