Congress has the power to remove issues from the Supreme Court. In other words they can say that the Court may not make decisions on a law they pass regarding marriage.
Is that where that Congressional power comes from? I have never looked it up but have heard both liberal and conservatives admit it is so.
Yes, look in post 16.
In most matters the Supreme Court acts like an appellate court, and Congress can make an exception to anything they rule on if they choose to.
The power is there, if Congress chooses to use it.
Article III Sec 1- “The judicial Power of the United States, shall be vested in one supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish.” Congress can tell the courts what their jurisdiction can and cannot be. If they actually wanted to. Cruz is going in the right direction.