Christ's anointing teaches you the truth on everything you need to know about yourself and Him, uncontaminated by a single life. Live deeply in what you were taught.
1 John 2:27
In the Old Testament times, pouring olive oil on something or someone was a sign that what was being anointed was being set apart for God's special use. High priests, rulers, and objects used in God's temple were all anointed and viewed as sac red. Jesus himself was often referred to as the Anointed One, which is the meaning of Messiah in Hebrew and Jesus in Greek.
Through Jesus' sacrifice, you too have become an anointed one. Instead of being anointed by oil, you have been anointed with god's own Spirit. You've been set apart for God's use int he is world. In the Old Testament, God occasionally anointed people like David and Saul with the gift of his Spirit. But before Jesus came to earth, this kind of anointing wasn't permanent. God's Spirit could be taken away, like it was from the ruler Saul when Saul became lax in how he followed God.
Thanks to Jesus, the anointing of God's Spirit will never be taken away from you. God's spirit set you apart and become your personal teacher and trainer. He helps you understand Scripture, see things more clearly from God's perspective, and discern between God's truth and religious-sounding lies. However, you can only experience a part of God's Spirit while you're here on m earth. That means your understanding of God, the Bible, and his ways is still imperfect. But God's Spirit will help lead you where you need to go in this life.