I love this verse: I memorized it when I was young and it has stuck.
When thou passest through the waters, I will be with thee; and through the rivers, they shall not overflow thee: when thou walkest through the fire, thou shalt not be burned; neither shall the flame kindle upon thee. Isaiah 43:2
I like memorizing passages or chapters, but there is a particular discipline with memorizing single verses with their reference. I had about 100 I memorized and reviewed for a few years in my teen years and most of them are still with me 30 years later.