Priscilla and Aquila were, according to the Apostle Paul's Letter to the Romans, his "helpers… who have for my life laid down their own necks." The 1st-century married couple is mentioned six times in the New Testament, always together, and most often with Priscilla's name first: she was, it's widely understood, the better teacher.
So significant a thinker was Priscilla that many contemporary biblical scholars believe she, not Paul, wrote the book of Hebrews. The book, rather unusually, does take the form of an unsigned letter, suggesting that its author's identity might have been suppressed by the early church.
Back in the 3rd century, Origen speculated that Hebrews's "phraseology and construction are those of someone who remembered the Apostle’s teaching and wrote his own interpretation of what his master had said." Recent authors like Ruth Hoppin have even identified, in the book's literary style and occasionally submissive tone, what they take to be evidence of a feminine point-of-view.
In all of Rome, Priscilla's catacombs are the oldest and best preserved, and they feature a number of interesting frescos: a woman, perhaps, being ordained by a bishop; a woman, perhaps, breaking the Eucharist bread; and, indisputably, the oldest known image of the Virgin Mary, nursing the baby Jesus.