Guilt

Since we have authorization for free access to enter the sanctuary by the blood of Jesus, by the fresh and living way that he opened up for us, through the curtain—that is through his flesh,
let us draw near with a sincere heart in the assurance that faith brings,
because we have had our hearts sprinkled clean from a burdened conscience and our bodies washed in pure water.
And let us hold unwaveringly to the hope that we confess, for the one who made the promise is trustworthy.

The Most Important 8 Verses in Hebrews, and maybe the Bible —The New Covenant. Heb pt.8 (8:6-13)

When you really understand the New Covenant, it will transform your life, bring you into a new freedom, and enrich your relationship with God.
Sadly it is rarely explained, and most Christians are not entirely free from the Old.