What does 24-36 mean in a religious context?
References to Biblical passages do not use page numbers as you would use in referring to other books. The reason for this is that there are so many different editions and translations of the Bible that page 50 in one Bible might be page 70 in another. Instead, the Bible is divided into books and those books are divided into chapters, and the chapters divided into verses.
Normally, as well as chapters and verses, you need the name of the actual Biblical book to identify a reference. However, "24-36" immediately suggests a famous passage from the Gospel of Matthew, the thirty-sixth verse of the twenty-fourth chapter, more properly referenced as Matt 24:36, in which Jesus says:
But of that day and hour knoweth no man, no, not the angels of heaven, but my Father only.
In this passage, Jesus is talking about the Apocalypse, or the end of this world as we know it, and the time when the various prophecies will be fulfilled. He is stating that no one but God the Father knows the precise date and time at which this will happen.