Hebrews 5:6
Ver. 6. As he saith also in another place,.... Or psalm; namely, in Ps 110:4 that is, the same person, even God the Father; who spake the words before cited, also expressed the following:
thou art a priest for ever, after the order of Melchisedec; that the psalm, from whence these words are taken, belongs to the Messiah, See Gill on "Mt 22:44" and this very passage is applied unto him by the Jewish writers {c}; and had not this been the general sense of the Jewish church at this time, the apostle writing to Hebrews would not have produced it; and it very clearly expresses the priesthood of Christ, the eternity of it, and the order according to which it was; and it being not according to the order of Aaron, but of another, shows the change of the priesthood, and so of the law; of Melchizedek, See Gill on "Heb 7:1"
{c} Moses Hadarsan apud Galatin. l. 10. c. 6. Abot R. Nathan, c. 34.