"The author of Hebrews is arguing that God himself has brought about the fulfillment of these institutions through his Son's priesthood, his once-for-all sacrifice, and the new covenant he inaugurated in the last days. These new institutions are never denied the Jews. In fact, the context of the epistle presumes that these are primarily for the Jews, considering that the author was speaking to a Jewish-Christian community. The author is not arguing for the abandonment by God of the Jewish people, but rather for the abandonment of the shadowy means by which God's people drew near to him. It is here we can speak of a qualified supersessionism. According to the author of Hebrews, the Levitical priesthood, the Mosaic covenant, and the Levitical sacrifices have been superseded by Jesus' priesthood, the new covenant, and Jesus' once-for-all sacrifice.
"However, we conclude that the polemical passages in Hebrews do not promote hatred of the Jews, nor do they advocate the destruction of the Jewish people. Rather, the author of Hebrews stresses the fulfillment of specific Jewish institutions for the benefit of the Jews. It is this idea of fulfillment that rules out the charge that the epistle promotes the supercession of the Jewish people. Because of God's great love for his people, he has provided a superior way by which his people can draw near to him."
--from the Conclusion