I’ve been dipping in and out of John Webster’s book Holiness. His account of a trinitarian theology of holiness is very satisfying. Viewing God’s holiness as being expressed in his acts, the relational aspect of God’s holiness is key to Webster’s treatment.
…God’s holiness is not simply to be associated with his transcendence, but equally with his condescension. 45
God's holiness cannot be isolated from God’s calling of a people….This unbreakable link between holiness and covenant is crucial, because it articulates how God’s holiness is not an abstract and oppositional attribute but a relational one, the ground of the free and merciful relation of the righteous God to his people. The holiness of the covenant creating God cannot be expounded as if it were simply a kind of moral purity that keeps itself aloof from all pollution. 46