I have been reading Joan E. Taylor’s The Immerser: John the Baptist within Second Temple Judaism. In “Chapter Two: Immersion and Purity” she juxtaposes John’s baptism with ritual cleansing at Qumran (e.g., 1QS). She quotes Josephus’ comments about John Antiquities 18.116-117:
(116) Now, some of the Jews thought that the destruction of Herod’s army came from God, and that very justly, as a punishment of what he did against John, that was called the Baptist; (117) for Herod slew him, who was a good man, and commanded the Jews to exercise virtue, both as to righteousness towards one another, and piety towards God, and so to come to baptism; for that the washing [with water] would be acceptable to him, if they made use of it, not in order to the putting away [or the remission] of some sins [only], but for the purification of the body; supposing still that the soul was thoroughly purified beforehand by righteousness.
There are similarities between John’s baptism and ritual cleansing in 1QS, namely that both understand baptism to be something that follows the cleansing of the soul, and cleansing of the soul happens through righteous actions: in the case of 1QS obedience to the Law as interpreted by the Teacher; in the case of John as exemplified through virtue, righteousness toward others, and piety toward God. For both John and 1QS the body could be contaminated through unrighteousness, but the soul cannot be cleansed through baptism. So one must first cleanse one’s soul through righteous action, then, and only then, the washing ritual would make one pure in body.
This brought to mind 1 Peter 3:21 where the author states explicitly of baptism that saves that it is “not the removal of dirt from the flesh, but an appeal to God for a good conscience through the resurrection of Jesus”. If most ritual cleansings were for the express purpose of making the body ritually clean so that the body could “catch up” with the soul (if you will), then is 1 Peter aiming to imply a direct contrast? If so, what does this mean for Christian baptism?
 Flavius Josephus and William Whiston, The Works of Josephus: Complete and Unabridged (Peabody: Hendrickson, 1987).
 For an analogous ritual remember various placed in the Gospels where Jesus and the Pharisees argue over rituals like washing one’s hands before a meal.