In which (to wit, soul or spirit) also he came, and preached to those spirits who were in prison. The true and common interpretation of this place seems to be, that the soul of Christ, after the separation from the body and before the resurrection, descended to a place in the interior parts of the earth, called hell in that which we call the apostles' creed, (sometimes called Abraham's bosom, sometimes Limbus Patrum, who would not take warning from his preparing and building the ark, but it may be reasonably supposed that many of them repented of their sins when they saw the danger approaching, and before they perished by the waters of the deluge, so that they died at least not guilty of eternal damnation; because, though they were sinners, yet they worshipped the true God, for we do not find any proofs of idolatry before the deluge. These then, and all the souls of the just, Christ descended to free from their captivity, from their prison, and to lead them at his ascension triumphant ...
Of things in heaven, because He was born, the Word of God, before all (ages); and of things on earth, because He became man in the midst of men, to re-create our Adam through Himself; and of things under the earth, because He was also reckoned among the dead, preaching the Gospel to the souls of the saints.
Spirits that were in prison: See here a proof of a third place, or middle state of souls: for these spirits in prison, to whom Christ went to preach, after his death, were not in heaven; nor yet in the hell of the damned: because heaven is no prison: and Christ did not go to preach to the damned.
With the same law of His being He fully complied, by remaining in Hades in the form and condition of a dead man; nor did He ascend into the heights of heaven before descending into the lower parts of the earth, that He might there make the patriarchs and prophets partakers of Himself.