In Hebrew, a matbil is one who immerses or baptizes.
Catholics usually call him John the Baptizer, rather than John the Baptist, because some Baptists imagine that he was the first Protestant Baptist. Of course, Protestants didn’t arrive on the scene at all until the 1500s, about the time of William Shakespeare.
Catholic tradition holds that Rabbi Yokhanan HaMatbil was born without the stain of original sin. The stain is passed along through the generations. Yokhanan’s aba, father, Zechariah, and his ima, mother, Elizabeth, were both righteous before God Lk 1:6, but baby Yokhanan was conceived with the stain of original sin, as we all are. Only Rabbi Yeshua and the Blessed Virgin Mary were conceived without the stain of original sin.
Rabbi Lucas tells us that “In those days Mary arose and went with haste into the hill country, to a city of Judah, and she entered the house of Zechariah and greeted Elizabeth” Lk 1:39–40. Mary was at that time pregnant with Rabbi Yeshua.
Rabbi Lucas continued, “And when Elizabeth heard the greeting of Mary, the child leaped in her womb; and Elizabeth was filled with the Holy Spirit” Lk 1:41. These two events have led to a tradition in which New Advent’s Catholic Encyclopedia says,
Now during the sixth month, the Annunciation had taken place, and, as Mary had heard from the angel the fact of her cousin’s conceiving, she went “with haste” to congratulate her. “And it came to pass, that when Elizabeth heard the salutation of Mary, the infant” — filled, like the mother, with the Holy Ghost — “leaped for joy in her womb,” as if to acknowledge the presence of his Lord. Then was accomplished the prophetic utterance of the angel that the child should “be filled with the Holy Ghost even from his mother’s womb.” Now as the presence of any sin whatever is incompatible with the indwelling of the Holy Ghost in the soul, it follows that at this moment John was cleansed from the stain of original sin. When “Elizabeth’s full time of being delivered was come … she brought forth a son (Lk 1:57);” and “on the eighth day they came to circumcise the child, and they called him by his father’s name Zachary. And his mother answering, said: Not so, but he shall be called John. And they said to her: There is none of thy kindred that is called by this name. And they made sign to his father, how he would have him called. And demanding a writing table, he wrote, saying: John is his name. And they all wondered” (Lk 1:59–63). They were not aware that no better name could be applied (John, Hebrew; Jehohanan, i.e. “Jahweh hath mercy”) to him who, as his father prophesied, was to “go before the face of the Lord to prepare his ways; to give knowledge of salvation to his people, unto remission of their sins: through the bowels of the mercy of our God” (Lk 1:76–78). Moreover, all these events, to wit, a child born to an aged couple, Zachary’s sudden dumbness, his equally sudden recovery of speech, his astounding utterance, might justly strike with wonderment the assembled neighbors; these could hardly help asking: “What can one, think ye, shall this child be?” (Lk 1:66).
Rabbi Yokhanan HaMatbil’s cleansing from the stain of original sin, however, was a baptism like ours, unique only in the sense that he was baptized in his mother’s womb. He was cleansed of the stain of original sin, but not of a propensity for evil. He is a saint in heaven because he largely overcame the temptations of sin.