Śaṅkara and later Advaita teachers set out four qualifications needed before the study of Vedānta can bear fruit: discrimination between the eternal and the passing; dispassion; the six virtues of calm, self-control, withdrawal, forbearance, faith and concentration; and an intense longing for liberation.
Sādhana-catuṣṭaya
The fourfold qualification of the seeker in Advaita: discrimination, dispassion, six virtues and longing for liberation.
Also: four qualifications