Ante-Nicene Fathers, Vol VII:
The Teaching of the Twelve Apostles: Chapter VII.—Concerning Baptism

Chapter VII.—Concerning Baptism.

1. And concerning baptism, 2441 thus baptize ye: 2442 Having first said all these things, baptize into the name of the Father, and of the Son, and of the Holy Spirit, 2443 in living water. 2444 2. But if thou have not living water, baptize into other water; and if thou canst not in cold, in warm. 3. But if thou have not either, pour out water thrice 2445 upon the head into the name of Father and Son and Holy Spirit. 4. But before the baptism let the baptizer fast, and the baptized, and whatever others can; but thou shalt order the baptized to fast one or two days before. 2446  

Footnotes

Verse 1 is found, well-nigh entire, in Apostolic Constitutions vii. 22, but besides this only a few words of verses 2 and 4. The chapter has naturally called out much discussion as to the mode of baptism.  

[Elucidation I.]  

Matt. xxviii. 19.  

Probably running water.  

The previous verses point to immersion; this permits pouring in certain cases, which indicates that this mode was not unknown. The trine application of the water, and its being poured on the head, are both significant.  

The fasting of the baptized is enjoined in Apostolic Constitutions, but that of the baptizer (and others) is peculiar to this document.