'Oil' in the Bible

Then Samuel took the flask of oil, poured it on his head, kissed him and said, “Has not the Lord anointed you a ruler over His inheritance?

Now the Lord said to Samuel, “How long will you grieve over Saul, since I have rejected him from being king over Israel? Fill your horn with oil and go; I will send you to Jesse the Bethlehemite, for I have selected a king for Myself among his sons.”

Then Samuel took the horn of oil and anointed him in the midst of his brothers; and the Spirit of the Lord came mightily upon David from that day forward. And Samuel arose and went to Ramah.