One of the uses of olive oil in biblical times was medicinal (see Luke 10:34). In this instance it cannot be concluded that the oil was used as medicine. There is another use that fits this occasion. Anointing with oil was a symbolic action to express amongst other things: joy or honour (see Psalm 45:7, Isaiah 61:3), and the blessing of God when a leper was healed (Leviticus 14:15–18).
The anointing with oil therefore served as a symbol of God’s care, restoration, and blessing.1
13 Ils chassaient beaucoup de démons, et ils oignaient d'huile beaucoup de malades et les guérissaient.