Yes.
Purgatory does not teach that a time of waiting or purifying occurs before judgment. Judgment occurs at the point of death in Catholic theology.
You seem to think that the verses you quoted mean that once a person gets saved, that there is nothing that he could do, other than unbelief, that could cause him to lose his salvation. But that that is not the point of the text, unless your read it out of context.
Let's keep reading the chapter:
26 For if we go on sinning deliberately after receiving the knowledge of the truth, there no longer remains a sacrifice for sins, 27 but a fearful expectation of judgment, and a fury of fire that will consume the adversaries. 28 Anyone who has set aside the law of Moses dies without mercy on the evidence of two or three witnesses. 29 How much worse punishment, do you think, will be deserved by the one who has trampled underfoot the Son of God, and has profaned the blood of the covenant by which he was sanctified, and has outraged the Spirit of grace? 30 For we know him who said, “Vengeance is mine; I will repay.” And again, “The Lord will judge his people.” 31 It is a fearful thing to fall into the hands of the living God.
The person in verse 29 was sanctified by the blood of the covenant, but if he goes on sinning deliberately, no sacrifice remains for his sins, and he will have a fearful expectation of judgment and fire. So that makes it rather clear that your reading of the text is incorrect.
I also note that the text states "He adds I will never again remember their sins and their lawless acts." The text does not state "He adds I will never again remember their sins
, except for the sin of unbelief, and their lawless acts." You had to read an exception into the text that is not present in the text, in order to attempt to maintain an interpretation of the text that is consistent with your theology. The fact that you need to read things into the text that the text does not teach, is a good reason to believe that your interpretation of it is incorrect.
Please take a look at Hebrews 9:23, and note that the text says "sacrifice
s". In your view, for what purpose does our Lord Jesus perform "sacrifice
s" in the Heavenly Sanctuary, if all of a person's sins are forgiven at the point that he is saved? What is the reason for the sacrifices?
Amen. But neither of these verses are inconsistent with purgatory. Even you believe that there is sanctification that occurs after a person that is saved. The fact that Christ died once for sins is not inconsistent with the idea that a person needs to be corrected and sanctified after he is saved. We disagree upon the timing of it.
I agree that Jesus paid for all of our sins "past, present and future", but Sacred Scripture does not teach that all of a person's sins "past, present, and future" are forgiven at the moment that he is saved.
That is quite obvious from the Lord's Prayer. Our Lord Jesus instructs us to pray the Lord's Prayer, and in the Lord's Prayer we ask for forgiveness of our sins. There would be no need to ask for forgiveness of them if they were already all forgiven at the moment that we became saved. Our Lord Jesus does not instruct us to do things for no reason.
And if you study the portions of Hebrews that I discussed above, especially considering the question of why Jesus performs heavenly sacrifices, you should understand why your view of things is incorrect.
God will most certainly forgive us for the sins that we commit in the future, but we have to ask for forgiveness to the extent that we are able. There is nothing in Sacred Scripture that teaches that we should presume on God's mercy for all of our wicked sins today, and that we do not even need to ask for forgiveness of our future sins, because we were saved at a certain point in time in the past. The only way that a person can reach such conclusions is by proof-texting.