Charles H. Spurgeon on Psalms 89:27

I will make him my firstborn. First, because he is first in the order of predestination; for it is through him, as through the head, that we are predestinated, as we read in Eph 1:1-23. Secondly, because he is first in the second generation to life everlasting, whence he is called (Col 1:18.) the firstborn from the dead, and in Re 1:5, the first begotten of the dead; and, thirdly, because he had the rights of the firstborn; for he was appointed heir of all things; and he was made not only firstborn, but also, high above the kings of the earth; that is, Prince of the kings of the earth, and King of kings. —Bellarmine.