Final answer:
The Old Deluder Satan Act was passed to promote public education, ensuring that children could read and write, especially the Bible, to prevent Satan from keeping them ignorant of religious texts.
Step-by-step explanation:
The Old Deluder Satan Act was passed by Massachusetts's colonists with a significant educational objective in mind. The key purpose of the act was to promote public education. This law emerged from a Puritan belief that literacy was essential for reading the Bible, which in turn was deemed crucial for both education and salvation.
In accordance with this act, it was mandated that towns with a population of fifty families should provide an elementary school. Those with more than a hundred families were required to establish a grammar school. The act aimed to ensure that children could read and write, thereby preventing Satan, the 'old deluder,' from keeping them from the knowledge of the Scriptures, as the Puritans saw it.