"Others are not in a position to receive it, perhaps on account of infancy, or some perfectly involuntary circumstance through which they are prevented from receiving it, even if they wish. ...and that [they] will be neither glorified nor punished by the righteous Judge, as unsealed and yet not wicked, but persons who have suffered rather than done wrong. For not every one who is not bad enough to be punished is good enough to be honoured; just as not every one who is not good enough to be honoured is bad enough to be punished."
St Gregory Nazianzen Oration 40 on Holy Baptism (which is the work cited in the Summa in the article on limbo of the infants)
https://www.newadvent.org/fathers/310240.htm
