Sforno on Leviticus 9:4/ספורנו על ויקרא ט׳:ד׳

1כי היום ה' נראה אליכם, it had already become manifest as an appreciation of their handiwork when we read that the Presence (glory) of the Lord filled the Tabernacle (Exodus 40,34). It is therefore no more than appropriate that you express your appreciation of this by this sacrifice.