I think that the idea of God being "wrathful," mirrors some of the ideals of the Roman Empire. The Catholics interpretation of the bible comes from a point in society in which there was a societal need for the control of the lower class of people. The lower class prays to Mary, and the other Saints in order to create a kind of hierarchy in which their prayers are "heard" and then relayed to Jesus and God. Those practices eventually led to the Reformation, and then the formation of the Protenstant church and even further to the different denominations we have today. Such as the Baptists. It may not be the most literal interpretation of the bible, but it doesn't go to say that Catholics love God or Jesus any less than other denominations. I have Catholic friends who adore God, and have given themselves to him completely.