Joshua said, or rather had said, to wit, the day before their passage; for it follows, to-morrow. Sanctify yourselves, both in soul and body, that you may be meet to receive such a favour, and with more attention and reverence observe and ponder this great work, and fix it in your hearts and memories. See Poole on "Exodus 19:10"; See Poole on "Leviticus 20:7".
Related Commentaries of Joshua 3:5
Joshua 3:5
5 And Joshua said unto the people, Sanctify yourselves: for to morrow the LORD will do wonders among you.