Luke 1:58

58.And her neighbors and relatives heard It may admit of doubt, whether the wonderful kindness of God was estimated by those persons from the simple fact of her being blessed with a child, or whether they had previously heard that an angel appeared to Zacharias, and promised to him a son. This was certainly no ordinary divine favor, that, out of the course of nature, a barren woman at a very advanced age had brought forth a child. It is possible that, on this ground alone, they magnified the divine goodness. On the eighth day, from a sense of duty or from courtesy, as is customary on such occasions, some people assemble; but God takes occasion from it to make them witnesses and spectators of his power and glory. There can be no doubt but the extraordinary birth brought a greater crowd. They had reckoned it a prodigy to see an old and barren woman suddenly become pregnant; and now that the child is born, their astonishment is renewed and increased. We infer from the words of Luke that, though they circumcised their children at home, they were not wont to do so without collecting a numerous assembly: and with good reason, for it was a common sacrament of the church, and it was not proper to administer it in a secret or private manner.