Westminster Larger Catechism

The only Mediator of the covenant of grace is the Lord Jesus Christ,¹³⁷ who, being the eternal Son of God, of one substance and equal with the Father,¹³⁸ in the fulness of time became man,¹³⁹ and so was and continues to be God and man, in two entire distinct natures, and one person, forever.¹⁴⁰