“How great” is “the multitude of sweetness, which God has hidden for those who love him” (Ps. 30:20). “He has hidden,” it says. Therefore, why marvel if any lover of the world does not know that which God has hidden for those who love Him?
[…] For it is manna, hidden and completely unknown except to those who taste it. For it is such sweetness of the heart, and not of the flesh, that no carnal person whomever is able to have known it. “You have put joy in my heart” (Ps. 4:7).
Corporeal delights, like the body itself, can be seen by the bodily eyes; eyes of the flesh cannot see the delights of the heart and also not even the heart itself. Therefore by what way could he know spiritual delights unless he makes a point of entering into his heart and dwelling within?
Therefore it is said to him: “Enter into the joy of your Lord” (Matt. 25:21). This inner joy is for spiritual persons. That sweetness which is felt within is that son of Leah…. For joy is one of the principal affections….
However, when it has been set in order, this can rightly be numbered among the sons of Jacob and Leah. For we certainly have ordered and true joy when we rejoice concerning true and inner goods.
The Apostle wished to animate us to the desire for such offspring when he said: “Rejoice in the Lord always, again I say rejoice” (Phil. 4:4). And the Prophet: “Rejoice in the Lord and exult you just, and glory all you with an upright heart” (Ps. 31:11).
For such offspring Leah gladly despised the mandrakes so that she would be able to have such a son. In fact, the mind that delights in the praise of men does not deserve to experience what inner joy is.
However, after the birth of Gad and Asher, Leah rightly gave birth to such a son because except by means of abstinence and patience the human mind cannot reach true joy.
Therefore it is necessary that he who wishes to rejoice concerning the truth exclude not only false pleasure but also vain disquiet. For he who until now delights in the lowest things is especially unworthy of inner enjoyment, and he who is disquieted by vain fear is not able fully to enjoy spiritual sweetness.
Truth condemned false joy when he said: “Woe to you who now laugh” (Luke 6:25). He extirpated vain disquiet when he admonished his hearers, saying: “Do not fear those who kill the body, for they are not able to kill the soul” (Matt. 10:28).
Richard of St Victor (d. 1173): The Twelve Patriarchs, c. 36,translated by Grover A. Zinn, Paulist Press @ Lectionary Central.