Ambrose of Milan

The laurel and the palm are the symbols of victory. The heads of the victors are crowned with laurel, and the hand of the conqueror is adorned with a palm. Hence the Church says: "I said, I will go up to the palm tree, I will take hold of its branches." Seeing the excellence of the Word and hoping that she can ascend to His height and the summit of knowledge, she says: "I will go up to the palm tree," so that she may leave behind all lower things and strive for higher things, for the reward of Christ, so that she may enjoy and taste …

The Six Days of Creation ↗

Bede

And the smell of your breath is like apples, etc. Indeed, in the smell of the mouth is the fame of good speech, and in the throat, however, is the very duty of voice dedicated to God. Both are worthy of praise in the Catholic Church, and both in every elected soul, because the voice itself, which teaches those present, and the fame of speech, which reaches the absent, whether through letters or through those who have heard, is proven to be full of virtue and grace. …

Commentary on the Song of Songs ↗

Robert of Tombelaine

He spoke truly, and ascended: because just as before the ages he determined to die for our death, so at the end of the world, merciful and faithful, he fulfilled it. Therefore he ascended the palm tree and took hold of its fruits: because, suspended on the cross, he found fruit, took hold of it, and bestowed it upon us. …

Commentary on the Song of Songs, Chapter 7 ↗