Manual tasks bring their own special blessings; in contrast with the more intellectual ones, they make it easier to guard the mind, the nous, and to pray the Jesus Prayer without interruption.
When a person is idle and not working, his intellect and his mind are completely free and unbridled. While at first this might seem like a good thing, it is indeed fraught with spiritual dangers. Since fallen human nature is so easily drawn towards sin, it is very difficult to guard the rational areas of the soul from demonic attacks and suggestion when it is idle.
Similarly, when a person is working intellectually – when writing or speaking, for example – the intellect and the mind are occupied with the task at hand, making it much more difficult for the mind to also be occupied with prayer.
When a person is doing a manual task, however, even if the intellect must be involved to a certain degree, the mind is still mostly free to pray. On Mount Athos, when the monks are involved in manual tasks, they take advantage of this situation by quietly saying the Jesus Prayer out loud in order to help the mind stay focused on prayer. They quietly and continuously pray, “Lord Jesus Christ, have mercy on me”, which is the shortest and therefore easiest form of the Jesus Prayer for the mind to hold on to.
This practice helps clear the mind, frees it from temptations and the passions, and fills the mind and heart with God’s grace. For this reason, many are happy to be assigned to manual tasks, such as with the harvesting of grapes (as shown here in the photo) which the monks participate in with the blessing of the Abbot.