Hebrews 10:12

But this man
Jesus Christ, for he is a man, though not a mere man; or this great high priest, who came to do the will of God, and whose body was offered once for all:

after he had offered one sacrifice for sins;
the sacrifice of himself, body and soul, and this but once:

for ever sat down on the right hand of God;
as having done his work effectually, and that with acceptance; and therefore is placed as a token of honour at the right hand of God, where he sits enjoying rest, ease, and pleasure, and that for ever; all which is opposed to the priests under the law; they were many, he but one; they offered many sacrifices, he but one; they offered theirs often, every day, he but once; they stood ministering, he sat down; his sacrifice being effectual to take away sin, when theirs was not.