Being mentally silent was not an activity that I had even thought about until I was thirty-three years old and participating in a twelve-step recovery program. People kept talking about "meditating" as part of their daily prayer time. I remember thinking about this as an activity to be practiced. It was an action that I needed to do so I created a "meditation wall" in my tiny apartment.
The meditation wall consisted of a Serenity Prayer plaque, a plaque of Proverbs 3:6, and framed slogans. Each day I would sit on the couch and read my meditation wall. Then I would think about what each one said and what it meant. One day, I realized that meditating wasn't me talking to myself, it was a time for me to be still, or silent. Wow! I had not tried to be mentally silent in a VERY long time.
Today, I am in awe of the Lord and trying my best to not sin. At days end, in bed, I search my heart, or review my actions and behaviors of the day. Then, I am silent.