What is the best fasting?

Question:
If I fast on the thirteenth, leave the fourteenth, fast on the fifteenth, and leave the sixteenth, is this considered the fasting of Dawud (peace be upon him)?

Answer:
The fasting of Dawud (peace and blessings be upon him) was that he would fast one day and break the fast the next day, all his life. He did not single out three days of the month; rather, he would always fast, fasting one day and breaking the fast the next. This is the best of fasting.
If a person wants to fast three days of every month, or fast the white days, that is also among the recommended practices (sunnah). The Prophet (peace and blessings be upon him) advised fasting three days of every month, because one good deed is rewarded ten times over. So if a person fasts three days of the month, it is as if he fasted the whole month. However, the more one increases in fasting until it reaches the fasting of Dawud, the better it is and the greater the reward. What is disliked or prohibited is for a person to fast all his life and never break the fast. That is what is prohibited. When some of the Companions said, "As for me, I will fast and not break the fast," the Prophet (peace and blessings be upon him) said, "As for me, I fast and I break the fast," and . Yes.