Leviticus 14:51

⁵¹ And he shall take the cedar-wood, and the hyssop, and the scarlet, and the living bird, and dip them in the blood of the slain bird, and in the running water, and sprinkle the house seven times:

Wall, rampart, gates, and bars

In Lamentations 2:8-9, the 'wall,' 'rampart,' 'gates,' and 'bars' signify doctrines.