There are two options for today's solemnity.
The Lord opened the doors of heaven and rained down manna upon them to eat; he gave them bread from heaven; man ate the bread of angels, alleluia.
As He fed the Israelites during their wandering in the desert, so does He feed us with, but with something more than manna. What the angels can only see, we can actually take within us.
Moses consecrated an altar to the Lord, and presented thereupon burnt offerings and sacrificial victims; he made an evening sacrifice as a fragrant offering to the Lord, in the presence of the Sons of Israel.
This is one of the options for the Offertory during the 24th. Sunday in Ordinary Time. A prefiguring of the Last Supper and Calvary, this is but a shadow of the Holy Sacrifice of the Mass.