Psalms 24: 1
לְדָוִד מִזְמוֹר ה’ הָאָרֶץ וּמְלוֹאָהּ תֵּבֵל וְיֹשְׁבֵי בָהּ
A Psalm of David: The earth and everything in it is G-d’s, the land and all who dwell in it.
Psalm 24 is designated as the Psalm of the Day for Sunday, which is the first day of the week. The Talmud (Rosh Hashana 31a) tells us it’s because the psalm says that “earth and everything in it is G-d’s.” The first day was when G-d created the world and established His ownership over it.