Allow me to repeat two sentences from the first reading.
“They worship in a copy and shadow of the heavenly sanctuary, as Moses was
warned when he was about to erect the tabernacle.
For God says, ‘See that you make everything according to the pattern shown
you on the mountain.’”
As a follow up on that, check with Chapter 36, 37, and 38 of Exodus. Those chapters in detail specify the type, the amounts and the dimensions of the brass, the acacia wood, and the linen that were to go into the temple.
That first sentence I quoted above gives the reason the pattern had to be followed to the T. They were to “worship in a copy and a shadow of the heavenly tabernacle.”
The Jews seemed to have felt that their temple was an exact copy of the house in which God lived in heaven. We can see that in Chapter Six of the Book of the Prophet Isaiah. When Isaiah had a vision of God in heaven he saw God above the heavenly temple’s altar with the train of his garment filling the temple up there. (There were even hot coals on the altar.)
Because the Jews felt that their temple was God’s house they imagined he was around every corner listening to their whispers.
God wanted people to think he was waiting for them in the temple. I think he wants us to think of each Catholic Church as his own house.
Once I asked sixth graders for a written answers to the question: “Is a church God’s house where we should keep quiet?” One girl answered, “I belong to a Holiness church, and we shouldn’t keep quiet, but a Catholic church is God’s house, and we have to be quiet there.”