Terce

Terce, or Third Hour, is a fixed time of prayer of the Divine Office in almost all the Christian liturgies. It consists mainly of psalms and is said at 9 a.m. Its name comes from Latin and refers to the third hour of the day after dawn.

The origin of Terce, like that of Sext and None, to which it bears a close relationship, dates back to Apostolic times. According to an ancient custom of the Romans and Greeks, the day and night respectively were divided into four parts of about three hours each. The second division of the day contained the hours from about the modern nine o'clock until about midday; using the Roman numbering the hour just preceding this division was called hora tertia (the third hour) from which the word terce is derived. Since the Roman day was divided into twelve hours from sunrise to sunset regardless of day length, the timing for hora tertia depended on the latitude and day of year. At Rome's latitude hora tertia was in modern terms 09:02 to 09:46 solar time at the winter solstice, but at the summer solstice it was 06:58 to 08:13.

These divisions of the day were also in vogue among the Jews at the time of Christ. In the New Testament we find mention of the sixth hour in Matthew 20:5; and of the ninth hour, in Matthew 27:46. The Holy Ghost descends upon the Apostles on the day of Pentecost at the third hour, Acts 2:15. Some of these texts prove that these three hours were, in preference to others, chosen for prayer by the Christians, and probably also by the Jews, from whom the Christians appear to have borrowed the custom.

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