Attitudes toward ecological consumption can trigger environmentally responsible intentions and behaviors. Understanding how ecological messages can influence attitudes is essential to mitigate climate change. This paper analyzes how religious affiliation (or lack of), can influence attitudes toward green advertising and explores the role of religious affiliation in the effectiveness of ecological messages. The findings indicate that religious affiliation has an influence on the degree of effectiveness of each message. So, green communications can be a useful tool to persuade atheists to develop more sustainable attitudes when they are exposed the benefits that can be achieved with green behavior. However, persuasive environmental messages, in general, do not generate major changes of attitude among Catholics. Businesses, NGOs, states, educators and society in general should acknowledge that environmental discourses fostering sustainable behavior. Furthermore, messages depicting the problems of environmental behavior have no repercussion on atheists and little on Catholics.