The document discusses the authenticity of Mark 16:9-20 in the Bible. It summarizes that while some of the oldest Greek manuscripts from the 3rd and 4th centuries CE do not include these verses, the majority of later Greek manuscripts and translations in other languages do contain them. It also notes that early Church fathers, such as Irenaeus, quoted from these verses, indicating they were present in the texts during the 2nd century CE. Therefore, while some verses were possibly added later to complete the ending, there is significant evidence that early Christians accepted Mark 16:9-20 as authentic parts of Scripture.