Don't whistle before you are out of the woods proverb
Don't conclude a problem solved until it is completely resolved.
"Your heart operation was successful. You are no longer in any danger" - "There might be some complications. Don't whistle before you are out of the woods".
"The problem will be solved if he agrees to help us." - "Don't whistle before you are out of the woods".
If you have something on your person/body, it means that you are carrying it with you.
Customs officers found a gun concealed about your person.