John Lightfoot on Luke 8:18

[For whosoever hath, to him shall be given.] God's measure is not like the measure of flesh and blood. The measure of flesh and blood is this: An empty vessel is receptive, but a full one can take in no more. But God's measure is this, The full vessel is receptive of more, but the empty vessel receives nothing; according as it is said, If hearing thou wilt hear; that is, If thou hearest thou shalt hear; if thou dost not hear, thou shalt not hear. The Gloss is, "If thou accustom thyself to hear, then thou shalt hear, and learn and add." That is not much unlike Beracoth, fol. 55. 1: "God doth not give wisdom but to him with whom is wisdom already."