Maryam and Zakariyya fasting and not speaking
20-4-2008 | IslamWeb
Question:
Asslamu Alaikum wa rahmatullahi wa barakatu i was wondering when Allah commanded Prophet Zakariya (AS) not to speak for three days before the coming of Yahya (AS) and when Maryam (AS) was also commanded not to speak after the birth of Isa (AS), was this like a fast during their times? jazakallhu Khairan
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
The scholars 
stated that in the legislation at the time of Maryam (Mary) and Zakariyya (Zachariah), may Allaah exalt their mention, when they fasted, they would neither eat nor speak, as mentioned by Ibn Katheer 
when interpreting the saying of Allaah (which means): {And if you see from among humanity anyone, say, ‘Indeed, I have vowed to the Most Merciful abstention, so I will not speak today to [any] man.’}[Quran 19:26]
However, you should know that when Zakariyya (Zachariah) 
abstained from speaking, he did not do so as an act of worship. Rather, it was beyond his control and was a sign for him indicating that his wife became pregnant. Allaah Says (what means): {He said, “My Lord, make for me a sign.”}[Quran 3:41], meaning a sign indicating that I will have a son. {He said, “Your sign is that you will not [be able to] speak to the people for three days except by gesture.}[Quran 3:41], meaning that you will only be able to gesture to people and you will not be able to speak to them despite the fact that you are in sound and good health; this is the same thing as in the verse of Allaah (which means): {He said, “Your sign is that you will not speak to the people for three nights, [being] sound.}[Quran 19:10]; as interpreted by Ibn Katheer .
However, the fasting of Maryam (Mary), may Allaah exalt her mention, was an act of worship and the wisdom thereof is to show that she was virgin and innocent of illegal sexual acts, when she would point to ‘Eesa (Jesus) and he would speak in the cradle and explain his situation to the people.
Allaah Knows best.