The defensive walls of a city necessarily had gates for those coming and going; gates were subject to enemy assault and were therefore also specially defended (2 Chron. 26: 9). Even so an enemy might destroy the gate (Judg. 9: 49, 52). Several of the gates of Jerusalem are mentioned in the account of the rebuilding of the city by Nehemiah. In the NT the Beautiful Gate of the Temple is mentioned in Acts 3: 2.
Markets were placed outside gates which therefore became the centre of commercial and social life, and also the place for legal decisions (Ruth 4). There the unemployed queued for work (Matt. 20: 3).
The ‘gates of hell’ which will not prevail against the Church (Matt. 16: 18) is an idiom for death (Ps. 107: 18; Job 38: 17).
Subjects: Architecture — Medieval and Renaissance History (500 to 1500).