Do banks check with employers when you buy a new house?

[Mindfullness]

In short, we are relocating but need my current salary to buy a new property.
My concern is I do not want my employers to find out until the sale has completed.
We have a large deposit (300k) so am hoping this will go in our favour?
Any advice gratefully received xx

In some circumstances the lender will ask for employers reference or letter from employer.