He didn't really hack it: he (or someone) seems to have left an "Easter egg" in it.
In 1604, at the Hampton Court Conference, King James I of England called upon the scholars of the day to produce an Authorized Version of the Bible. This eventually appeared in 1611 and is known as the King James Version.
Dr. Laurence Vance has written an articulate and concise history of the events leading up to the indroduction of the KJV.
Shakespeare lived from 1564 until 1616. In 1610, when he would have been 46 years old, he was possibly one of the scholars engaged in rendering the Biblical text into the very nice English of the day. The Bible was considered to be the Word of God, so none of these scholars was about to receive any credit for his work, which probably didn't seem very fair to The Bard, who was fond of seeing his name in print.
Let's take a look at Psalm 46. If we count 46 words in from the beginning, and 46 words in from the end, what do we find? Don't count the "Selah" at the end which isn't really part of the Psalm, it's likely some sort of musical notation (there's a scene that deals with this in East of Eden) .