First word-complete sincerity and openness. Even the holiest and wisest confessor cannot forcibly pour into the soul what he desires if it is not sincere and open. An insincere, secretive soul risks great dangers in the spiritual life, and even the Lord Jesus Himself does not give Himself to such a soul on a higher level, because He knows it would derive no benefit from these special graces.
Second word-humility. A soul does not benefit as it should from the sacrament of confession if it is not humble. Pride keeps it in darkness. The soul neither knows how, nor is it willing, to probe with precision the depths of its own misery. It puts on a mask and avoids everything that might bring it recovery.
Third word-obedience. A disobedient soul will win no victory, even if the Lord Jesus himself, in person, were to hear its confession. The most experienced confessor will be of no help whatsoever to such a soul. The disobedient soul exposes itself to great misfortunes; it will make no progress toward perfection, nor will it succeed in the spiritual life. God lavishes His graces most generously upon the soul, but it must be an obedient soul. (Divine Mercy in My Soul, 113)
Sincerity. Openness. Humility. Obedience.
Virtues for those who strive for sanctity.