The Church recognizes that sovereign Christ can draw anyone to Heaven even without His sacraments, which are given us following His ascension, so that we may have eternal life. The baptism, the confession and the Eucharist are ordinary means of grace; in extraordinary circumstances extraordinary events happen. For example, the Church recognized several catechumens, that is, unbaptized candidates for baptism, as martyrs and saints, based on that teaching.
Impossible! Christ didn't mean what He said. Jean Cauvin knows better than that!