Adam Clarke's Commentary on the Bible - Luke 1:21
The people waited - The time spent in burning the incense was probably about half an hour, during which there was a profound silence, as the people stood without engaged in mental prayer. To this there is an allusion in Revelation 8:1-5 . Zacharias had spent not only the time necessary for burning the incense, but also that which the discourse between him and the angel took up. read more
Adam Clarke's Commentary on the Bible - Luke 1:20
Thou shalt be dumb - Σιωπων silent; this translation is literal; the angel immediately explains it, thou shalt not be able to speak. Dumbness ordinarily proceeds from a natural imperfection or debility of the organs of speech; in this case there was no natural weakness or unfitness in those organs; but, for his rash and unbelieving speech, silence is imposed upon him by the Lord, and he shall not be able to break it, till the power that has silenced him gives him again the permission to... read more