Luke 1:21

And the people waited for Zacharias, and marvelled that he tarried so long in the temple.

The congregation waited outside the temple while Zacharias remained inside beyond the expected time, marveling and wondering at his prolonged tarrying. They were waiting to learn whether God had given a visible sign of approval, and his long delay made them fear that God had shown displeasure instead. The delay came because Gabriel spoke to him in the holy place, where he stood before the golden altar as the cloud of incense with the prayers of Israel ascended, and became conscious of a divine presence. The angel stood on the right side of the altar, a position indicating favor, but Zacharias took no note of it.

His priestly duty was to pray for pardon for the people's public and national sins and for the coming of the expected Saviour, for whom he had prayed for many years, and heaven had now sent its messenger to announce that those prayers were about to be answered. The mercy of God was too great for him to credit, so he was filled with fear and self-condemnation in unbelief. As the penalty for his unbelief temporary dumbness came upon him, so that after the angel left he could not speak when he tried to pray. When he came out to the congregation he could not speak or pronounce the usual benediction or address the people, but could only spread out his hands and look up to heaven. His shining face showed he had encountered the angel, so the people perceived he had seen a vision in the temple. Sudden muteness after doubting God's power, followed by the loosing of the tongue, presents such affliction and restoration as a sign of God's action, as echoed when a person struck dumb had speech restored the next morning.