Joshua 8:31

As Moses the servant of the Lord commanded the children of
Israel, as it is written in the book of the law of Moses
( Deuteronomy 27:5 ) ;

an altar of whole stones, on which no man hath lift up [any] iron;
(See Gill on Exodus 20:25), (See Gill on Deuteronomy 27:5), and, (See Gill on Deuteronomy 27:6):

and they offered thereon burnt offerings unto the Lord, and sacrificed
peace offerings;
by way of thanksgiving for the good land they were introduced into, and this was what they were ordered to do by Moses, ( Deuteronomy 27:6 Deuteronomy 27:7 ) .