Apologeticus (Latin: Apologeticum or Apologeticus)[1] is a text attributed to Tertullian according to Christian tradition,[2] consisting of apologetic and polemic. In this work Tertullian defends Christianity, demanding legal toleration and that Christians be treated like all other sects of the Roman Empire. It is in this treatise that one finds the sentence "Plures efficimur, quotiens metimur a vobis: semen est sanguis Christianorum," which has been liberally and apocryphally translated as "the blood of the martyrs is the seed of the Church" (Apologeticus, L.13). Alexander Souter translated this phrase as "We spring up in greater numbers the more we are mown down by you: the blood of the Christians is the seed of a new life,"[3] but even this takes liberties with the original text. "We multiply when you reap us. The blood of Christians is seed," is perhaps a more faithful, if less poetic, rendering.
There is a similarity of content, if not of purpose, between this work and Tertullian's Ad nationes—published earlier in the same year—and it has been claimed that the latter is a finished draft of Apologeticus. There arises also the question of similarity to Minucius Felix's dialogue Octavius. Some paragraphs are shared by both texts; it is not known which predated the other.
Tertullian's brief De testimonio animae ("Concerning the Evidences of the Soul") is an appendix to the Apologeticus, intended to illustrate the meaning of the phrase testimonium animae naturaliter christianae in chapter 17).