The record is clear that members of Congress were legislating a particular religious view of marriage.
MORE: https://www.au.org/blogs/wall-of-separation/strike-down-doma-federal-marriage-law-violates-church-state-separation
See also...
High Noon At The High Court: Supreme Court Takes Up Marriage Equality
https://www.au.org/blogs/wall-of-separation/high-noon-at-the-high-court-supreme-court-takes-up-marriage-equality
Nonbelievers Tell Supreme Court: Declare DOMA and Prop 8 Unconstitutional
http://www.americanhumanist.org/news/details/2013-03-nonbelievers-tell-supreme-court-declare-doma-and-pro?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+AmericanHumanistNews+
How the Court Could Rule on Same-Sex Marriage (Chart)
http://www.nytimes.com/interactive/2013/03/24/us/how-the-court-could-rule-on-same-sex-marriage.html?smid=tw-nytimes&_r=0