63 To prayer must be added frequent and fervent use of the Sacrament of Penance which, as a spiritual medicine, purifies and heals us; likewise it is necessary to receive the Eucharist, which as Our predecessor of happy memory Leo XIII asserted, is the best remedy against lust. The more pure and chaste is a soul, the more it hungers for this bread, from which it derives strength to resist all temptations to sins of impurity, and by which it is more intimately united with the Divine Spouse; "He who eats my flesh and drinks my blood, abides in me and I in him."
Source: Sacra Virginitas (Vatican.va)