The sin atonement providing the forgiveness of sin for Israel was never dependent upon the congregation but upon the sin offering of the priest (Lev 4:20). Therefore without a priest there would be no forgiveness (Num 15:28); but this was to the exclusion of willful sins (Num 15:30) because “presumptuous” sin confirms the individual’s absence of faith in God’s word.
This is why Christ is the Priest of those who believe in Him. Thus forgiveness in the admission (confess) of sin (1 John 1:9) is made available by the priestly atonement of Christ, who is the “High Priest” (Heb 3:1) of His “Body, the Church” (Col 1:18).
It may not be realized that God’s eternal covenant made with Abraham and his descendants did not come by the Law because “the promise” was made and settled “four-hundred and thirty years” prior to giving of the Law (Ten Commandments/sacrificial ordinances, etc.—Gal 3:17), which Law changed nothing concerning the promise.
As it can be easily understood, Christ’s priesthood is not after the Law which, “was added because of transgressions, till the seed should come” and also so “that the offence might abound” (Gal 3:19; Rom 5:20). To be a priest under the Law one would need to be from the tribe of Levi after the Aaronic order and Christ was after the tribe of Judah, thus the works of the believer does not attain or retain his standing in the Father (only reveals it). The believer’s place is determined by Christ’s Cross-work which makes, “us accepted in the Beloved (Jesus)” (Ehp 1:6).