The Court, like many other parts of the government, has systematically increased its power and influence over the years.
No matter what your opinion is on the recent gay marriage rulings, you should read the dissenting opinions that warn of the new power the court has ruled for itself through the decisions.
Scalia’s dissent is wonderfully written and very much worth reading (whether or not you agree with him, as you say). I cannot offer the same praise for the other two.
Better yet, don't - they're talking a load of self-serving bullshit. Scalia and the other justices who wrote dissenting opinions in that case were quite happy to overrule Congress a day earlier and declare that the Voting Rights Act no longer necessary. Their interest in restricting the reach of the Supreme Court only applies to overturning laws they don't like.
No matter what your opinion is on the recent gay marriage rulings, you should read the dissenting opinions that warn of the new power the court has ruled for itself through the decisions.