It is the responsibility of the abbot and prioress to announce, day and night, the hour for the Opus Dei. They may do so personally or delegate the responsibility to a conscientious member, so that everything may be done at the proper time.

Only those so authorized are to lead psalms and refrains, after the prioress or abbot according to their rank. No monastics should presume to read or sing unless they are able to benefit the hearers; let this be done with humility, seriousness, and reverence, and at the bidding of the prioress or abbot.

The word conscientious, these days, may mean that we are scrupulous and hardworking. These may be, however Benedict does not necessarily mean these. More practically, here the conscientious are those who know the importance of doing all that can be reasonably done to ensure that everyone arrives in good time for communal prayer. This can be done best by someone attentive to the needs of others, someone who has an appreciation of rhythm and routine as a support to prayer.

We can also include the word conscience here. To be someone of good conscience is about having a sense of what is appropriate in any given moment. People such as these are discerning, they are about serving the time of prayer rather than inserting themselves into prayer. People such as this serve the Work of God, they are not caught in themselves. 

In life, our attention will be caught in ego, often in subtle ways, ways that may not be noticed by us. In community, these ways are often noticed by others. These ways can be enduring, being a catalyst for a loving response; they can also be experienced by some as annoying; and they can sometimes be a difference between moving more deeply into God or not. For example, perhaps it is somehow important that I always whistle, or maybe in social company I tend to always talk about the same two or three things. To be growing conscientiously means that the permanence of things like these to personality and existence is, over time, breaking down.     

Things can go unnoticed because attention, that which would otherwise help us to know where our ego tendencies are, is itself caught in ego. This is a kind of blindness. However, thanks to the practice of meditation and community, attention can incline to the heart and the experience of ego is, over time, revealed. It is a revelation via experience, we do not make it up ourselves. An awareness grows of the subtleties of attachment, of what we unknowingly cling to. This is what it is to become conscious and to grow in good conscience.   

When members are becoming conscious in this way, there is less and less chance that the subtleties of egoic focus and opinion will leak into prayer and become established. Instead, reverence and sincerity can grow thanks to prayer being established as a humble practice. All this is not self-limiting; self-expression and creativity are not curtailed. Instead, the deeper and true self is expressed because humility and reverence have helped throw off a cloak of self-focus. The whole of us is then free enough to go to Jesus in prayer. As we pray and meditate our heart-sight is returned, and we see the ways we have been blind.

They came to Jericho. As Jesus and his disciples and a large crowd were leaving Jericho, Bartimaeus the son of Timaeus, a blind beggar, was sitting by the road. When he heard that it was Jesus the Nazarene, he began to shout, “Jesus, Son of David, have mercy on me!” Many scolded him to get him to be quiet, but he shouted all the more, “Son of David, have mercy on me!” Jesus stopped and said, “Call him.” So they called the blind man and said to him, “Have courage! Get up! He is calling you.” He threw off his cloak, jumped up, and came to Jesus. Then Jesus said to him, “What do you want me to do for you?” The blind man replied, “Rabbi, let me see again.” Jesus said to him, “Go, your faith has healed you.” Immediately he regained his sight and followed him on the road. (Mark 10: 46-52, NET).