Matthew Poole and continuators on Hebrews 1:9

9 Thou hast loved righteousness, and hated iniquity ; therefore God , even thy God hath anointed thee with the oyl of gladness above thy fellows .

The Administration of this King in his Kingdom is suitable to his Throne and Scepter, it is all Goodness. For he so loved Righteousness and hated Iniquity (being Righteous and Holy in himself, in Life and Death, expiating Sin, and sanctifying Believers.) So that he acts as to both of these properly from himself, perfectly and for ever.

It may be a reason why he so loved Righteousness, being anointed, or of his unction, because he loved the one, and hated the other; therefore God the Son is the Person to whom the Father speaketh this.

God the Father, his God in respect of the Humane Nature, Luke 1.35. Formed by him, Gal. 4.4. As Mediator between God and Sinners, Iohn 20.17. The Head of the Church, in Covenant with God, his great Gospel-Minister.

So his Father anointed him with the Holy Ghost and with Power, Iohn 3.34. Acts 10.38. And thereby as endowed, so exalted him above all Kings and Prophets who were literally anointed, and above all Angels, having Divine Power and Authority supereminent to all communicated to him, enjoying the best and highest Joy in all his transactions with the Father for us, and which may perfect Joy in us, Iohn 15.11. and 17.13.

The Coheirs of his Kingdom, beyond whatever God communicated to Saints or Angels; he had not the Spirit by measure, Iohn 3.34. What others enjoy, it is from his fulness, Iohn 1.16. Luke 4.18, 19, 21.