John Calvin Commentary Hebrews 9:7

"but into the second the high priest alone, once in the year, not without blood, which he offereth for himself, and for the errors of the people:" — Hebrews 9:7 (ASV)

For himself and for the errors of the people, or for his own and the ignorances of the people. The verb shagag in Hebrew means to err or to mistake, and so shgagah, derived from it, properly denotes error or mistake. Yet it is generally taken for any kind of sin; and doubtless, we never sin except when deceived by the allurements of Satan.

The Apostle does not understand this to mean mere ignorance, as some say; on the contrary, he also includes voluntary sins. But, as I have already said, no sin is free from error or ignorance. For however knowingly and willfully anyone may sin, he is nevertheless so blinded by his lust that he does not judge rightly or, rather, forgets himself and God. For men never deliberately rush headlong into ruin but, being entangled in the deceptions of Satan, they lose the power of judging rightly.