By and large I thoroughly enjoy your articles, Dan. This one confuses me a bit more because it seems a little off target in several cases. Sure, "Christianity" doesn't appear in the Bible, but Acts, where mention of the name "Christians" first appears (11:26, as you note) is primarily about the spread of the good news beyond its original Jewish context--that's the whole debate of Acts 15. There's no indication that the term "Christians" was pejorative: it could just as easily have been the name chosen by the non-Jewish faithful to indicate who they were. And by extension, "Christianity," whether the word appears or not, would have been what they were doing. Paul seems to be carving out a similar non-Jewish space in I Corinthians for what would be "Christianity."
Similarly, as you note, "discipleship" as an abstract noun does not appear, but "disciple" appears regularly. I'm not quite sure of your point here. Μαθητής (Mathētēs) is the Greek word translated as "disciple," and they both fundamentally mean "learners" (μαθ- being a root of the Greek verb "to learn" and disc- being the Latin root for the same, as I'm sure you know.) In the New Testament, the disciples were above all those who learned, whether from Jesus directly or later from others. Sure, contemporary applications of the term may not draw from that same well of "learning," but that's not the same as suggesting that the concept of discipleship, as an abstract description of being a disciple, is absent from the Bible.
Some similar objections could be made to "rapture," "problem," and "solution." The words may not appear in the Bible, but that does not mean that ideas related to those words are absent from the Bible.
To give a parallel example from the ancient world that has caught my attention: the Romans had no word for "political protest." Granted, the Roman world had no experience of social activism as we know it in 2021, but Roman history is fairly full of examples of "protest," sometimes violent, occasionally effective. So let's not get hung up on words, but let's not suggest that the absence of particular words is equivalent to the absence of an experience or a reality.
Peace, brother.
