In the 1940s, renewed interest arose in this area. Using the argument of baptism by desire, some theologians speculated that God in His mercy would look favorably upon the desire for salvation of the Church, the family, the unbaptized infant, and even of Himself, and welcome the unbaptized child to Heaven. Here again the Magisterium provided succinct guidance. Pope Pius XII asserted that “an act of love can suffice for an adult to acquire sanctifying grace and supply for the lack of baptism; to the unborn or newly born infant, this way is not open” (Acta Apostolicae Sedis, XLIII, 84). Later in 1958, the Holy Office (now the Sacred Congregation for the Doctrine of the Faith) admonished, “The practice has arisen in some places of delaying the conferring of Baptism for so-called reasons of convenience or of a liturgical nature” a practice favored by some opinions, lacking solid foundation, concerning the eternal salvation of infants who die without Baptism. Therefore this Supreme Congregation, with the approval of the Holy Father, warns the faithful that infants are to be baptized as soon as possible…" (Acta L, 114). Again, the Magisterium neither defined nor rejected the idea of limbo.