Answer: Our Mediator was called Christ, because he was anointed with the Holy Ghost above measure₁; and so set apart, and fully furnished with all authority and ability₂, to execute the offices of prophet₃, priest₄, and king of his church₅, in the estate both of his humiliation and exaltation.

1. John 3:34; Psalm 45:7
2. John 6:27; Matthew 28:18-20
3. Acts 3:21-22; Luke 4:18,21
4. Hebrews 5:5-7; Hebrews 4:14-15
5. Psalm 2:6; Matthew 21:5; Isaiah 9:6-7; Philippians 2:8-11

For further study see:

1. WSC Q21: Who is the Redeemer of God’s elect?
2. WSC Q22: How did Christ, being the Son of God, become man?
3. WSC Q23: What offices doth Christ execute as our Redeemer?
4. WSC Q24: How doth Christ execute the office of a prophet?
5. WSC Q25: How doth Christ execute the office of a priest?
6. WSC Q26: How doth Christ execute the office of a king?
7. WSC Q27: Wherein did Christ’s humiliation consist?
8. WSC Q28: Wherein consisteth Christ’s exaltation?