In the third appointment of the series of lectures on the mystery of the Eucharist, Fr Luca Refatti presented the thought of the medieval theologian Thomas of Aquino. After briefly introducing the figure of Thomas, Luca Refatti compared the Eucharistic mystery with other sacraments and analysed the concept of transubstantiatio (change of substance). Finally, two important distinctions made by St Thomas in relation to the Eucharist are analysed: the distinction between sacramental communion and spiritual communion, and the distinction between sacrament and sacrifice.

Luca Refatti has been a Dominican friar since 2011 and has been living in Istanbul for 7 years.