When our souls have roamed in meditation through a spiritual garden, we can choose two or three ideas that seemed most helpful and think about them occasionally all day long. Birds have nests in trees and can retire to them when need arises and stags have bushes and thickets where they take cover, hide, and enjoy the cool shade during the summer. There, as in a stronhold, they can defend themselves against temptations. Genuine devotion is simply honest love of God. Ostriches are not flying birds, chickens fly short distances with much effort, but eagles, doves, and swallows fly high and far.
Sinners are like the ostrich and are earthbound.
Good people who have not quite reached devotion are like the chicken. They fly in God's direction, but inefficiently and awkwardly. The devout soar to God with regularity. Devotion, then, is a natural agility of the spirit. Don't sow weeds in the soil of your heart.