Long things in a small list
The term "tabula rasa" means "blank slate."
Locke believed that each of us were born with a blank slate. This means that our minds, according to Locke, were entirely blank -- without rules, preconceptions, or information.
This slate would slowly be "filled in" by sensory experiences. Our sensory experiences, Locke believed, would add the information and the rules necessary to learn further.
Credible would be
Someone who's credible is honest and believable. ... Similar to words like reliable and plausible, credible is an adjective that comes to us from the Latin credibilis, meaning “worthy to be believed.” A credible reputation is often earned through consistent good behavior and an overall trustworthy personality.
You won't necessarily be safe. You'll only if you follow the instructions. But if you read and follow the instructions, it will keep you safe because you will be doing the right things. The instructions are to keep you safe.