Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
LXX

Exodus 16:29

See, for the Lord has given you this day [as] the sabbath, therefore he has given you on the sixth day the bread of two days: ye shall sit each of you in your houses; let no one go forth from his place on the seventh day.

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