Here are a few good quotes on the topic of humility from Calvin’s Institutes.
“No one is permitted to receive God’s blessings unless he is consumed with the awareness of his own poverty.”
“Augustine does not consider it humility when a man, aware that he has some virtues, abstains from pride and arrogance; but when man truly feels that he has no refuge except in humility.”
“Why do we presume so much on ability of human nature? It is wounded, battered, troubled, lost. What we need is true confession, not false defense.”
“But I require only that, laying aside the disease of self-love and ambition, by which he is blinded and thinks more highly of himself than he ought [cf. Gal. 6:3], he rightly recognize himself in the faithful mirror of Scripture [cf. James 1:22-25].”
“[Man] is so banished from the Kingdom of God that all qualities belonging to the blessed life of the soul have been extinguished in him, until he recovers them through the grace of regeneration. Among these are faith, love of God, charity toward neighbor, zeal for holiness and for righteousness.”