That statement perfectly encapsulates the problem. The Senator (I'm sure knowingly) is presenting her preferred version of Christianity, which includes the Ten Commandments and Christian prayer forced upon children. Because it's her version, it's the "right one."
Of course, anyone who does even a surface level of research knows that Christianity is full of varied experiences and interpretations. Many versions do not include the ten commandments as necessary guidance, and many do not believe in performative prayer or prayer that is not from the heart.
But the purpose is control, so all of that nuance is worth a hill of beans to people like the Senator. Christians who don't fall in line are no better than non-believers to them.