praeparator
From LSJ
τὸ δὲ ποιεῖν ἄνευ νοῦ ἃ δοκεῖ καὶ σὺ ὁμολογεῖς κακὸν εἶναι: ἢ οὔ → but doing what one thinks fit without intelligence is—as you yourself admit, do you not?—an evil
Latin > English (Lewis & Short)
praepărātor: ōris, m. praeparo,
I a preparer (eccl. Lat.): Joannes praeparator viarum Domini, Tert. adv. Marc. 4, 33.