Matthew 3:17 And suddenly a voice came from heaven, saying, “This is My Beloved Son, in whom I am well pleased.”
For you to stand up in front of a crowd and shout out about how pleased and happy you are about and for someone else may well take an extraordinary event.
God had no problem with shouting out about Jesus because this is His Son and He has lived a pretty extraordinary life so far.
Don’t forget Jesus came to John and asked that John baptize Him in the river. So this is God being very pleased because Jesus is setting a great example for everyone.