The Greek word APOSTASIA is used only twice in the New Testament. One is in Acts 21:21 where many are accusing the apostle Paul of "turning away" many from the teachings of Moses. The second is the turning away from "the faith" in 2 Thess. 2:3.
So there are two apostasies mentioned in the N. T. These will be delineated later. But first, let us take a look at the basic meaning of the word apostasy.
The word APOSTASIA in the Greek is feminine, but it comes from the neuter word APOSTASION, meaning "divorcement." The primary root word is APHISTEIMI, and it means basically "faithless." The connotation of the word is a turning from the right path, a perverting of the right way.
In opposition to apostasy are other scriptures which refer to a staying with the faith or protecting "the faith." In 2 Tim. 4:7 we read Paul's comment, ". . . I have kept the faith." The word for "kept" here in the Greek means "to stand a watch, to guard." Paul was responsible for and faithful to guard, not faith, but "the faith:" that body of divinity or doctrine that God has set down in his word.
In Acts 6:7 we read of priests' being "obedient to the faith." Notice this is not faith but "the faith." This word obedient in the Greek means to "hearken to a command." In other words, these priests were converted to the doctrines of Christ, and they obeyed Christ's commands and were faithful to that position.
Remember that in Acts 13:8 Elymas endeavored to "turn away" a deputy from "the faith." This Greek word is DIASTREPHO and means "to pervert, or to turn away from the right path" (Strong). Literally this word means "through turning."
The two apostasies are: (1) the turning away from the teachings of Moses, which Paul was accused of doing. Whether he actually did this or not may be debatable, but the word is nonetheless used in this situation, and (2) the apostasy of turning from "the faith" as we see happening even before the Bible is closed.
Next time the specifics of what this apostasy is will be considered.