'Sacrificing' in the Bible

After David had finished sacrificing the burnt offerings and peace offerings, he blessed the people in the name of the LORD of the Heavenly Armies

and Absalom sendeth Ahithophel the Gilonite, a counsellor of David, out of his city, out of Gilo, in his sacrificing sacrifices; and the conspiracy is strong, and the people are going and increasing with Absalom.