Several saints are called Doctors of the Church for the depth of their theological writings and the influence they continue to have in the life of the Church.
St. Bernard of Clairvaux is one of those Doctors of the Church, but many have called him a particular type of doctor.
Honey Doctor
Pope Pius XII wrote an entire encyclical dedicated to St. Bernard of Clairvaux entitled, Doctor Mellifluus, which can be translated the “Full of Honey Doctor” or “Honey Doctor”:
The “Doctor Mellifluus,” “the last of the Fathers, but certainly not inferior to the earlier ones,” was remarkable for such qualities of nature and of mind, and so enriched by God with heavenly gifts, that in the changing and often stormy times in which he lived, he seemed to dominate by his holiness, wisdom, and most prudent counsel. Wherefore, he has been highly praised, not only by the sovereign Pontiffs and writers of the Catholic Church
Part of the reason why he is called the “Honey Doctor” is because of his own use of honey as an analogy for wisdom, as Pope Pius XII explains:
In the following words, he describes most appropriately the doctrine, or rather the wisdom, which he follows and ardently loves: “It is the spirit of wisdom and understanding which, like a bee bearing both wax and honey, is able to kindle the light of knowledge and to pour in the savor of grace. Hence, let nobody think he has received a kiss, neither he who understands the truth but does not love it, nor he who loves the truth but does not understand it.
St. Bernard is also quoted in the document, writing, “Jesus is honey on the lips, melody in the ear, joy in the heart. Yet not alone is that name light and food. It is also a remedy. Is any one amongst you sad? Let the name of Jesus enter his heart; let it leap thence to his mouth; and lo! the light shining from that name shall scatter every cloud and restore peace.”
Honey is often used in reference to wisdom and as St. Bernard was widely known for his wisdom, it is a fitting nickname for the respected saint.