Why do Christians believe God knows everything?

Christians believe God knows everything about everybody, even the things other people cannot see, He even knows what people are thinking.

 
God knows what people are thinking
 

The Bible teaches that God knows all there is to know. In fact Christians believe that God knows more about people than they know about themselves. Talk about some of the things the children don’t know about themselves such as: what were their great, great Grandparents like? What will their job be when they are a grown up? What presents will they get for their next birthday? Ask the children if they think God knows the answers to these questions.

Explain that Christians believe that because God knows everything about everybody and everything, He always knows what is best for each and every person.