The onlookers were amazed after the Apostles were filled with the Holy Ghost; they wondered, saying one to another, What meaneth this? Others mocking said, These men are full of new wine. With the commonsense answer, These are not drunk as you suppose, seeing it is but the third hour of the day, St Peter went on to give his hearers a dogmatic discourse on the incarnation: it was not an uplift exhortation about moral values nor a fine frenzy, but a down-to-the-earth statement of historic fact, followed by the uncompromising advice, Do penance, ana be baptized every one of you. Then, he added, yon shall receive the gift of the Holy Ghost.There could be no more fitting preface to a series of studies, of which this is the first, on the seven Gifts of the Holy Ghost in the light of scientific Christian theology.