Francis Gigot, Catholic Encyclopedia (1913)
“ In their writings the Fathers of the Church mean by that expression sometimes the abode of the righteous dead before they were admitted to the Beatific Vision after the death of the Saviour, sometimes Heaven, into which the just of the New Law are immediately introduced upon their demise. When in her liturgy the Church solemnly prays that the angels may carry the soul of one of her departed children to "Abraham's Bosom", she employs the expression to designate Heaven and its endless bliss in company with the faithful of both Testaments, and in particular with Abraham, the father of them all. ”
