Should I give him half of the down payment

So my fiancé has been working diligently, [unbeknownst to me] to buy a home for our family. He’d been very sneaky lately and leaving a lot to “run errands”. I knew he was up to something.

Well yesterday he surprised me and took me to the lot that he is having our home built on. I was very shocked and happy. He showed me the floor plan and it’s going to be a beautiful home. It should be done in June/July.

So later that night he told me that if I want to refinance the home and get my name on it, I need to give him half of the down payment. The plan is for us to move in this summer and split the mortgage down the middle. And if I want my name on the house he says I need to give him half of the down payment.

I’ve never brought a home, never lived with a man etc. I just want to know if this is right. I honestly don’t think that I should have to give him any money. I will be his wife so why am I paying him as if it’s a business move? He said “marriage is a business in a aspect.”

I’m just confused because I thought once we were married our money was OUR money so why would I need to pay him half of the down payment? I thought just paying half the mortgage would be enough. Should I not get my name on he house and just pay half the mortgage with nothing to show for it? Or should I cough up half of the down payment on a home that HE picked and brought?