Hebrews 8:7

For if the first covenant had been faultless, there would have been no occasion for a second.

Hebrews 7:11

Further, if the Levitical priesthood had been the means of reaching perfection (for it was on the basis of that priesthood that the Law was enacted for the People), why was it still necessary for another sort of priest to emerge with the rank of Melchizedek, instead of simply with the rank of Aaron

Hebrews 7:18

A previous command is set aside on account of its weakness and uselessness

Galatians 3:21

Then the Law is contrary to God's Promises? Never! Had there been any law which had the power of producing life, righteousness would really have been due to law,

Hebrews 8:6

As it is, however, the divine service he has obtained is superior, owing to the fact that he mediates a superior covenant, enacted with superior promises.

Treasury of Scripture Knowledge

Summary

For if that first covenant had been faultless, then should no place have been sought for the second.

Bible References

Had

Hebrews 8:6
As it is, however, the divine service he has obtained is superior, owing to the fact that he mediates a superior covenant, enacted with superior promises.
Hebrews 7:11
Further, if the Levitical priesthood had been the means of reaching perfection (for it was on the basis of that priesthood that the Law was enacted for the People), why was it still necessary for another sort of priest to emerge with the rank of Melchizedek, instead of simply with the rank of Aaron
Galatians 3:21
Then the Law is contrary to God's Promises? Never! Had there been any law which had the power of producing life, righteousness would really have been due to law,