Theophany is a central concept in Eriugena’s spirituality and it has been comprehensively treated so far from a theoretical point of view. The present study aims at investigating John Scottus’s ‘practical’, i.e. ascetical, perspective. My hypothesis is that for Eriugena contemplation is always dependent on practice, to such an extent that his theophanic mysticism should be considered together with his asceticism. Given that John Scottus’s asceticism is not always systematically displayed, I assembled a number of ascetical aspects of his practical spirituality and organized them into two categories: (1) negative aspects of asceticism: repentance, purgation, mortification, and (2) positive aspects of asceticism: virtues, grace, and sacraments. All these ascetical aspects are presented in close connection to Eriugena’s ultimate spiritual purpose, which is attaining God in the highest theophanies.