Bernard of Clairvaux

In his own words on Deuteronomy

• Deuteronomy 6:5

  See for yourself if those three commands are not prescribed in the law when God says: "You shall love the Lord your God with your whole heart, your whole soul and your whole strength." It seems to me, if no more suitable meaning for this triple distinction comes to mind, that the love of the heart relates to a certain warmth of affection, the love of the soul to energy or judgment of reason, and the love of strength can refer to constancy and vigor of spirit. So love the Lord your God with the full and deep affection of your heart, love him with your mind wholly awake and discreet, love him with all your strength, so much so that you would not even fear to die for love of him. Your affection for your Lord Jesus should be both tender and intimate, to oppose the sweet enticements of sensual life. Sweetness conquers sweetness as one nail drives out another. No less than this keep him as a strong light for your mind and a guide for your intellect, not only to avoid the deceits of heresy and to preserve the purity of your faith from their seductions, but also that you might carefully avoid an indiscreet and excessive vehemence in your conversation. Let your love be strong and constant, neither yielding to fear nor cowering at hard work. Let us love affectionately, discreetly, intensely. We know that the love of the heart, which we have said is affectionate, is sweet indeed, but liable to be led astray if it lacks the love of the soul. And the love of the soul is wise indeed, but fragile without that love which is called the love of strength. So then, to love with your whole heart, your whole soul and your whole strength means not being led astray by allurements, or seduced by lies, or broken by injuries.

  Sermons on the Song of Songs, Sermon 20