In our case, murder being once for all forbidden, we may not destroy even the foetus in the womb, while as yet the human being derives blood from other parts of the body for its sustenance. To hinder a birth is merely a speedier mankilling; nor does it matter whether you take away a life that is born, or destroy one that is coming to the birth. That is a man which is going to be one; you have the fruit already in the seed.
TertullianIf the sky stands still, if the earth quakes, if there is famine, if there is pestilence, at once the cry is raised: Throw the Christians to the lions! So many to one?
TertullianBut now inquiry is being made concerning these issues. First, can any believer enlist in the military? Second, can any soldier, even those of the rank and file or lesser grades who neither engage in pagan sacrifices nor capital punishment, be admitted into the church? No on both counts.
TertullianThus the connection of the Father in the Son, and of the Son in the Paraclete, produces three coherent Persons, who are yet distinct One from Another. These three are one [thing], not one [Person], as it is said, 'I and my Father are One,' in respect of unity of substance not singularity of number.
Tertullian