testimony to an event of Christian conversion that has already occurred in some unmediated sense. In contrast to this vacuous but all too common assumption, Luke’s account of Peter’s appeal on the day of Pentecost is pregnant with expectation: ‘… you will receive the gift of the Holy Spirit … [t]he promiseis for you and your children and for all who are far off’. Baptism is approached with expectation because baptism is constituted by promise. As has already been noted, the sacraments are res promissa