Final answer:
Deuteronomy 24:19-21 commands the proper treatment of the poor and the foreigner by requiring the sharing of uncollected harvest remnants.
Step-by-step explanation:
The commandment in Deuteronomy 24:19-21 pertains to the treatment of the poor and the foreigner, requiring those who harvest crops to leave behind any sheaf not initially collected, as well as the olives that remain on the tree and grapes left in the vineyard after the harvest. This allows the poor and the foreigner to collect these remainders for their sustenance. This idea of social justice to care for the vulnerable members of society reflects the broader ethical and community values articulated throughout Deuteronomy and other Mosaic laws.