Psalms 85:2

Thou hast forgiven the iniquity of thy people, thou hast covered all their sin. Selah.

Thou hast forgiven the iniquity of thy people, thou hast covered all their sin. "Cover" [ kaacaah (H3680)] is the expression for "atone" - i:e., to hide out of God's view our sin by the reconciliation effected through the blood of Jesus (Psalms 32:1, note). The coats of skin used to cover Adam's nakedness after the fall, and provided by God, prefigures this atonement covering by Christ. They who will not have their sin covered by Messiah's blood shall in vain call to the mountains, "Cover us" (Hosea 10:8 - the same Hebrew verb; Revelation 6:16).