Ezekiel 16:9 NKJV
"Then I washed you in water; yes, I thoroughly washed off your blood, and I anointed you with oil."
The Lord used an example of a person that needed to be washed and ministered to as He described what He did for the Jews. After the woman in the story was washed with water, He anointed her with oil. Water can cleanse but it can leave the skin feeling dry.The anointing with oil after washing is like a finishing touch. It is soothing and refreshing.
Spiritual parallel: After we receive cleansing from whatever dirt or filth that was attached to us as a result of worldly contamination, we need to hang around for the Holy Spirit to anoint us. We need to receive God's love until we feel no dryness. After we are forgiven and cleansed, our enemy or our own minds can cause us to feel dry - undeserving of God's love. So we cannot stop with the washing. We must stay in God's presence for the finishing touch - the oil of the Holy Spirit's anointing.