Bede : In the first instance, we can understand this basin (or flanged bowl, as it is called further on) to be the water of baptism, in which all those who enter the doors of the church must bathe in order to be cleansed. It was put between the tabernacle of the testimony and the altar of the holocaust, and the priests were commanded to wash themselves in it twice a day (that is, morning and evening) when they were going to the altar of incense to offer to the Lord. We, however, are not supposed to be washed in the water of baptism more than once; consequently the basin commends to us that washing of compunction and of tears which is required of us at all times, and especially when we draw near to minister at the heavenly mysteries. — On the Tabernacle 3.14, AT Exodus 3:18-20