This is talking about man's anger, not God's. One that is in response to the challenge of God's word. One of the reactions that people have when they feel threatened is to hit out. To get angry. As God's word challenges people it will provoke some to anger.
Some people try to count to ten when they feel angry.
Just as a building is only as good as it's foundations, so is the way that we receive God's word. It has to be built on humility, that is to say thinking of God and His word more highly than ourselves. This can only come about through a change of heart inspired by God's Holy Spirit. Therefore, get rid of all moral filth and the evil that is so prevalent and humbly accept the word planted in you, which can save you. Verse 22 is the key to the whole letter of James.