Tertullian, On Baptism 14
They drag the Apostle's own words into court: "Christ did not send me to baptize" (1 Cor 1:17), as if that single line cancels baptism altogether. If the argument holds, why did he baptize Gaius, Crispus, and the whole household of Stephanas (1 Cor 1:14-16)? Even granting that Christ did not commission him personally to baptize, he had ordered the other Apostles to do exactly that. Paul wrote these words to Corinth under pressure; schisms and party spirit were tearing the church apart, some claiming Paul, others Apollos. To keep the peace and avoid looking like he was feathering his own nest, the Apostle says he was sent to preach, not to baptize. Preaching comes first, baptism follows; and I would argue that whoever is authorized to preach is also authorized to baptize.
Latin
Sed de ipso Apostolo revolvunt, quod dixerit: Non enim me ad tinguendum Christus misit, quasi hoc argumento Baptismus adimatur. Cur enim tinxit Gaium et Crispum et Stephanae domum? Quanquam etsi non eum miserat Christus ad tinguendum, tamen aliis Apostolis praeceperat tinguere. Verum haec pro conditione tunc temporis ad Corinthios scripta sunt, quoniam schismata et dissensiones inter illos movebantur, dum alius Paulo deputat, alius Apollo. Propter quod pacificus Apostolus, ne sibi omnia defendere videretur, non ad tinguendum ait se missum, sed ad praedicandum. Nam et prius est praedicare, posterius tinguere. Si prius praedicatum: puto autem licuit et tinguere cui licuit praedicare.