John Gill Commentary 1 Kings 2:26

"And unto Abiathar the priest said the king, Get thee to Anathoth, unto thine own fields; for thou art worthy of death: but I will not at this time put thee to death, because thou barest the ark of the Lord Jehovah before David my father, and because thou wast afflicted in all wherein my father was afflicted." — 1 Kings 2:26 (ASV)

And unto Abiathar the priest said the king
Who was either at court, or he sent for him, and thus addressed him:

get you to Anathoth ;
a city of the tribe of Benjamin, given to the priests, (Joshua 21:18) ; of which place Abiathar might be originally, and whither he is bid to return:

unto your own fields ;
which belonged to him there, either by inheritance or purchase; and these he was to mind, and not perform the functions of his office, however as high priest, and at Jerusalem, and the tabernacle there, and still less appear at court, or meddle with state affairs, only to attend to his private domestic concerns:

for you are worthy of death ;
in joining with Adonijah in the lifetime of David, and setting him up as a king without his knowledge, and in opposition to Solomon, contrary to the will of God, and promise of David, of which he, being high priest, cannot be thought to be ignorant, and for his late confederacy with Adonijah, of which Solomon had knowledge:

but I will not at this time put you to death ;
he does not give him a full pardon, only a respite; suggesting, that should he be guilty of any overt act, he would be put to death another time, though not now:

because you bore the ark of the Lord God before David my father ;
when he fled from Absalom, (2 Samuel 15:24) ;

and because you have been afflicted in all in which my father was
afflicted ;
shared with him in all his afflictions under the persecutions of Saul, from the time he slew the priests at Nob, and at the rebellion of Absalom; in each of which he accompanied him, and suffered and sympathized with him.