Pro 18:10 The name of the LORD is a strong tower: the righteous runneth into it, and is safe.
Pro 18:11 The rich man's wealth is his strong city, and as a high wall in his own conceit.
Remember when you were very small, and something frightened you? What did you do?
I remember practically climbing up my dad, knowing that his strong arms would hold me safe from whatever was threatening me, even if it was just the neighbors' son, brandishing his water gun. High above my would-be attacker, I could serenely smile, feeling safe and secure.
In the Old Testament, a refuge or fortress was a very real need. Un-walled villages snuggled around walled "stronghold" cities, where residents in the region would flee in times of trouble and war. High towers could be defended against an army many times the size of the force inside. If you were a villager and you heard rumors of an army on the march, it would bring you comfort to look over your shoulder and see that high tower that you would run to if necessary.
Our God, His name, and His promises, are a strong tower for us -- He is our safety and our security. Solomon contrasts the rich man, who can be tempted by his conceit and his wealth, to think that his riches and the power he has, will be his security and his safety.
I'm so glad that we can depend on our Lord, and on His promises, and feel the comfort of His arms to hold and shield us --- no matter what threatens us!