Read this passage and open each verse for the full verse feed and commentary tools.
11Now if there was perfection through the Levitical priesthood (for under it have the people received the law), what further need was there for another priest to arise after the order of Melchizedek, and not be called after the order of Aaron? 12For the priesthood being changed, there is of necessity a change made also of the law. 13For he of whom these things are said belongs to another tribe, from which no man has given attendance at the altar. 14For it is evident that our Lord has sprung out of Judah, as to which tribe Moses spoke nothing concerning priesthood. 15This is yet more abundantly evident, if after the likeness of Melchizedek there arises another priest, 16who has been made, not after the law of a fleshly commandment, but after the power of an endless life: 17for it is testified, "You are a priest forever, According to the order of Melchizedek."
18For there is an annulling of a foregoing commandment because of its weakness and uselessness 19(for the law made nothing perfect), and a bringing in thereupon of a better hope, through which we draw near to God. 20Inasmuch as it is not without the taking of an oath, 21for they indeed have been made priests without an oath; but he with an oath by him that says of him, "The Lord swore and will not change his mind, `You are a priest forever, According to the order of Melchizedek`".
22By so much has Jesus become the collateral of a better covenant. 23Many, indeed, have been made priests, because they are hindered from continuing by death. 24But he, because he lives forever, has his priesthood unchangeable. 25Therefore he is also able to save to the uttermost those who draw near to God through him, seeing he ever lives to make intercession for them. 26For such a high priest was fitting for us: holy, guiltless, undefiled, separated from sinners, and made higher than the heavens; 27who doesn`t need, like those high priests, to daily offer up sacrifices, first for his own sins, and then for the sins of the people. For this he did once for all, when he offered up himself. 28For the law appoints men high priests, having infirmity; but the word of the oath, which was after the law, appoints a Son, perfected forevermore.
Hebrews 7:11-28 (WEB)