wonders will never cease
US /ˈwʌn.dərz wɪl ˈnɛv.ər siːs/
UK /ˈwʌn.dərz wɪl ˈnɛv.ər siːs/

1.
used to express surprise, often with a hint of sarcasm, at something unexpected or unusual happening
:
•
He actually cleaned his room for once. Well, wonders will never cease!
•
You actually finished your homework on time? Wonders will never cease!