Virtue: When you recite: "In the name of Allah, I place my trust in Allah and there is no might nor power except with Allah."
The angel will say: "You shall be defended, protected and guided"
The meaning of this Dua is that you are asking Allah for His protection from the outer world as you have placed your trust in Him. And surely, Allah grants the one who asks for it.
Reference: Sunan Abu Dawood 5095