The ruling on voluntary fasting for one who has missed fasts to make up

Question: What is the ruling on voluntary fasting, such as the white days of Shawwal, the first ten days of Dhul Hijjah, and the day of Ashura, for one who has days from Ramadan that he has not made up?

Answer: It is obligatory for one who has missed fasts from Ramadan to begin with making them up before fasting voluntarily; because the obligatory is more important than the voluntary in the most correct of the opinions of the scholars.