You have something really special, maybe a favorite toy, a drawing notebook, a gift you got that you love a lot. What do you do with that special thing? You take care of it. You keep it. You protect it.
Now imagine that God gave you a treasure bigger than any toy: His teachings. The right things for living well, being honest, taking care of people, obeying with joy.
Solomon says: guard it like the most precious thing in your life. Don't throw it away. Don't forget it. Protect it like you protect what you love most.
You protect what you value. What you keep in your heart shapes who you are.