"Your oath on the Bible...."
The Museum has several Bibles in our Collection, even a mid-1700's Book of Common Prayer. When colonists arrived on America's shores, they brought more than their clothing and a few other possessions, they brought their heritage, their beliefs and traditions with them. Religion was deeply incorporated in colonial law (especially the Puritan's laws). Virginia law in 1662 required everyone to resort "diligently to their parish church" on Sundays "and there to abide orderly and soberly," on pain of a fine of fifty pounds of tobacco, the currency of the colony.  Colonial law and punishment was pretty gory at times and one role religion played was to try to steer colonists from making poor choices through fear of Hellfire and damnation, the pillory, stocks, dunking chair, etc.
The Bible was a vastly important item and a real and symbolic glue holding communities together. As an entity, the "Church" was quite powerful. Churches served as meeting houses and courts until such structures were erected. One of the traditions colonists brought with them was the use of a Bible to take oaths, to swear to the truth. At that time and into the 1900's, the very act of placing one's hand on the Bible and swearing an oath to be truthful was a momentous action. There were severe societal and sometimes even legal punishments for those who lied under an oath on the Bible.
Bibles have been used in courts of law well before the English colonies were established, the actual beginning of their use is not firmly known. This Bible was used in the Orange County Courthouse at least as early as October 2nd, 1929 until approximately the mid-1950's. The Bible was printed in England sometime between the 1880's into the early 1900's. The Bible was an important part of life as early as the Colonial Period well into the mid 20th century. Victorian Americans were especially dedicated to reading the "Good Book" along with other enriching and improving materials; at least those who could read and had the funds to purchase such items.
It was rather routine for Victorian Americans to carry small books of poetry or religious prose (for example) in their pockets (men/youth), (women/girls) work baskets or reticules. The book below, "Daily Guide" was printed around 1887 by T. Nelson & Sons. The intricately embossed book is 3 1/2" x 2 3/4". It has biblical quotes and readings to elevate one's thoughts and goals for the day.
The practice of a daily guide and biblical readings is still found in many faiths today that are still operational.
 James A. Cox. Colonial Crimes and Punishments | The Colonial Williamsburg Official History & Citizenship Site