@Pakbella and
@humy.11.23
When you receive your PR this mean you become PR of Canada.PR is a document which will help you come.back to Canada but you can go to Pakistan anytime.
When the PR card arrives you can send it to him by courier or if some relative is going , he can take the card to him.
Remember few things,
Your spouse has to accumulate 1095 days to be eligible for Citizenship
He/she if spending alot of time outside can also create problem in renewal of his PR status in future. This is why CIC always asking PR and citizen to show letter of intent of living in Canada if a PR or citizen is living outside and sponsoring someone .you can understand the idea from it.
Yes he can go and come back anytime after he enter Canada for first time.and complete all the documentation of his first entry. He is clear now for Canadian govt to come and go.
The good idea is to spend time inside Canada till citizenship and less outside.
But he can come and go anytime without restriction. Its better to keep an excuse in pocket for rainy days.
You dont know when the law change