My prayer life was transformed when I truly understood what this means:

And this is the confidence that we have toward him, that if we ask anything according to his will he hears us.1 John 5:14

Now, my prayers and life are shaped to be sensitive to God’s will, not trying to shape God’s will to my desires, because it is pointless and glorifies myself over Him.

Obedience and submission to God’s will can significantly reduce anxiety and leads to an even more joyful life. 

Note that I said ”joyful”, not happy. You don’t have to be in a happy state to be joyful in the Lord.