'Purifying' in the Bible

She shall continue in the blood of purification thirty-three days. She shall not touch any holy thing, nor come into the sanctuary, until the days of her purifying are completed.

For their office was to wait on the sons of Aaron for the service of the house of Yahweh, in the courts, and in the rooms, and in the purifying of all holy things, even the work of the service of the house of God;

because it doesn't go into his heart, but into his stomach, then into the latrine, thus purifying all foods?"

Now there were six water pots of stone set there after the Jews' way of purifying, containing two or three metretes apiece.