A press release states:
Lewis’ proposed legislation, designed to preserve equal dignity among branches of government, would only be applicable to rulings concerning the constitutionality of an Act of Congress following passage. Lewis, a strong supporter of numerous legislative measures aimed to define marriage as an exclusive union between a man and a woman, believes a more comprehensive solution is necessary to address the broader issue of activist courts; a concern he believes has troubling implications beyond just the issue of marriage.
Now, what's the point in allowing the Supreme Court to strike down laws as unconstitutional in the first place if a Congressional vote can override the decision? There have been a lot of very popular things which the Supreme Court has struck down and which, today, no one would think of defending - laws mandating segregation would be a good example.
The Supreme Court has the power to strike down laws as unconstitutional because, sometimes, a majority can use its political power in unjust ways - ways that go outside the boundaries of what they are allowed to do and/or ways which infringe upon the rights of minorities. Lewis' bill doesn't restore the "equal dignity" among the branches of government, but it would make it easier for legislative majorities to run roughshod over others.