I have long held the position that the majority of the Reformed were somewhat strange on merit (most 1689 Federalists do). I have argued elsewhere against the concept of proper/ontological merit in Christ because I don't think it makes much sense. In turn, I've long been a supporter of ex pacto merit and I think the best theologians on this were Frans Burman, Johannes Cocceius, Herman Witsius, and Thomas Boston. But a strange question arises for those who hold to ex pacto merit and hold that Christ merited for himself (as I hold along with Witsius and Burman. Voetius, Mastricht, and Heidegger also affirmed He merited for Himself). How exactly do we square Christ's merit by which He acquired right with the fact that He is God and thus already has a right to all things?
I think the answer can be put simply:
The right of Christ is twofold. The first is natural to Him by which all things are due as God. By this right, He always rules over all of creation. This is not merited. The second right is economic and merited by His actions as man. By this right, He merited "the glory of His body and whatever pertained to His outward excellence, as His Ascension, veneration, and the rest" as Aquinas stated (though I don't know why he adds "veneration"), and His lordship over the mediatorial kingdom.
The Reformed who argue against Christ meriting for Himself argue by making His divine right to all things meritorious of human rewards (thus they argue for example that Christ as God had a right to glorification from birth), but this does not follow because His divine right deals with His divine nature and the authority and lordship He possesses over all things by virtue thereof. He has always had this right and possessed the things it entitled Him to (nor could this ever be otherwise).
So I would not even say, as Duby does in his excellent book on Christology for example, that Christ possessed the right to the beatific vision since this pertains to his human nature. Rather, He earned the right to the beatific vision in His human nature. I cannot say he had the right to it since I want to affirm He had to earn this right.