ציטירנדיקער פּירוש אויף שמואל א 1:25

With three bulls: Some of them to eat and some of them to slaughter to the Lord. And likewise, "one ephah of flour," to eat and to offer a grain-offering from it; and likewise, "and a jar of wine," to drink and to pour [a libation] from it. Hence it stated (I Samuel 1:25), "And they slaughtered the bull," and it did not say, "the bulls" - meaning to say, the bull that they offered to the Lord.