Heb 10

10:26. BAGD says that "no sacrifice for sins remains" equals "no sacrifice for sins can be made" -- this accords well with the same use of the word, same TVM, "remains," there in Heb 4:6, where a future is being discussed. If we sin willfully as Christians, there is no sacrifice for sins that can be made in the future. There are no more sacrifices for sin coming down the pipe; cf. 9:28.

Thinking about Ps 95 in Hebrews 4, and seeing the phrase "since it remains for some to enter it" there in verse 6, the idea there is that Hebrews is explaining what 95:7-11 is talking about concerning God's rest.

Back in Heb 3:19, the exodus generation failing to enter Canaan is explained. Then Hebrews explains further about the rest from the fact that 95:7 addresses the readers of that psalm, long after Joshua (4:8), calling that time a "today." David "fixes a certain day, 'Today (4:7)'," the time of David's hearers. Hebrews explains that if Joshua had given them rest, David would not have spoken like that. The very fact that David addresses his hearers with a "today" makes the promise of rest apply to David's hearers, and by extension to the present hearers (4:3,9-11).

Hebrews then states that this "Sabbath rest" still remains "for the people of God." (4:9). Here is again the use of "remains" to refer to some future event in the plan of God. In 10:26 there is no sacrifice for sin that remains as a future event in the plan of God. It is not that sacrifices for sin that have already come about -- in particular, Christ's final sacrifice -- will be undone for certain people -- that would be an unfortunate ad hoc, an idea shoe-horned into the verse -- but that what he has been saying all along is continuing to be important for the readers -- the sacrifice for sin is Christ, since, among all the other reasons for Christ's excellence, also this reason exists too, that no sacrifice for sin remains to come in the future.