Where we are weak, God is strong in us, if we go to God for help. That strength is found in the church family, praying with people we love. That strength is found in the sacred writings which comfort our soul and give us direction in how to respond to tragedy, to grief for our nation and the victims of violence. God is not with us only in good times, but in the bad. Simply by turning to God and asking for help.
Anger is a result of fear.
If we have put our trust in God, we can be free from fear by believing that God hears and answers us, by believing that God will take care of us. We WILL not to fear. Yes, anger is a natural part of the grieving process. Use the power of anger for doing good, not for hurting human beings. Transform the fear and anger into good works.