Bede the Venerable — as excerpted in the Catena Aurea on Luke 13:18-21

“Now the man, is Christ, the garden, His Church, to be cultivated by His discipline. He is well said to have taken the grain, because the gifts which He together with the Father gave to us from His divinity, He took from His humanity. But the preaching of the Gospel grew and was disseminated throughout the whole world. It grows also in the mind of every believer, for no one is suddenly made perfect. But in its growth, not like the grass, (which soon withers,) but it rises up like the trees. The branches of this tree are the manifold doctrines, on which the chaste souls, soaring upwards on the wings of virtue, build and repose.”