Justification before God is strictly by His Blood.
Justification before God is strictly by the Blood of Christ ! Rom 5:9
9 Much more then, being now justified by his blood, we shall be saved from wrath through him.
This scripture is crystal clear on Justification by the Blood of Christ, and yes this is before the Justified ones believe on Christ.
This Justification by blood is based solely on the redemption that is in His Blood Rom 3:24
24 Being justified freely by his grace through the redemption that is in Christ Jesus:
24 [All] are justified and made upright and in right standing with God, freely and gratuitously by His grace (His unmerited favor and mercy), through the redemption which is [provided] in Christ Jesus,
The word freely in Rom 3:24 is the greek word dōrean and means:
I.freely, undeservedly
It also is translated and means:
for nought, without a cause.
So the Justification before God secured and applied to their accounts, is not based upon anything they did. If we make Faith/Believing a condition for it, we deny the Truth, as simple as that.
Its by the Redemption that is in His Blood, because attached with it is Forgiveness of sins Eph 1:7
7 In whom[By His Death] we have redemption through his blood, the forgiveness of sins, according to the riches of his grace;
This is all according to God's Grace. Justification is the result of the forgiveness of sins too, which is the result of the redemptive blood payment [ransom] to the Law and Justice of God, for all whom He died.
Redemption therefore is Justification through the Blood of Christ. Redemption is what Christ accomplished for the offences of those He died, and Forgiveness, Justification have been applied to their account. Now it has not yet been applied sensibly to them until they receive the notion of it by God given Faith, but before Faith the factuality of it has been applied in the courtroom of Heaven !