Exodus 29:4 meaning

In order to approach the holy God, one must be clean. That is why the first thing that had to be done before entering into the LORD's presence was to be washed. To do this, Moses was to bring Aaron and his sons to the doorway of the tent of meeting and wash them with water. Notice that this was to be done at the tabernacle's door as a demonstration that to enter the LORD's presence, one must be cleansed by removing the pollution that is the result of sin.

This principle applies to us as well (Heb. 10:22). The New Testament Church was cleansed by "the washing of water." In addition, washing is tied to regeneration in the New Testament (Titus 3:5). Jesus also washed the disciples' feet, showing that confession of sin, and the forgiveness it brings, is necessary to walk in fellowship with God (John 13:1-17). Jesus made it clear that forgiveness between humans is necessary to walk in fellowship with God (Matthew 6:14, 5:23-24).