Answer
In order to determine what is the shortest book of the Bible, first we must decide what method to use. Should we count by the number of verses in each book or by the number of words? The length of verses can vary significantly, so it would be more accurate to count by the number of words.
Second, should we count by the number of words in an English translation, or by the number of words in the original Hebrew and Greek? When translating from Hebrew or Greek into English, it can sometimes require multiple English words to translate a single word in Hebrew or Greek. So, it would be more accurate to count by the number of words in Hebrew and Greek, especially considering those are the languages God chose to record His breathed-out Word (2 Timothy 3:16–17).
By counting the number of words in Hebrew or Greek, the shortest book of the Bible is 3 John, which has 219 words. The second shortest book of the Bible is 2 John with 245 words. The third shortest book of the Bible is Philemon with 335 words in Greek. The fourth shortest book of the Bible, and shortest book of the entire Old Testament, is Obadiah with 440 Hebrew words. The fifth shortest book of the Bible is Jude with a count of 461 words.
Special thanks go to Logos Bible Software for making the determination of the shortest book of the Bible by Hebrew or Greek word count much easier.
