It seems that if God says that he would place good and evil before His people, and by making a responsible choice this should signify that God offers His grace necessary to observe the law and the people are able to accept the grace.
The responsibility and freedom of man is apparent elsewhere.
Isaiah 5: 1-7
Let me now sing of my friend,  my friend's song concerning his vineyard. My friend had a vineyard on a fertile hillside;  He spaded it, cleared it of stones, and planted the choicest vines; Within it he built a watchtower,  and hewed out a wine press. Then he looked for the crop of grapes,  but what it yielded was wild grapes. Now, inhabitants of Jerusalem and men of Judah, judge between me and my vineyard:  What more was there to do for my vineyard  that I had not done? ~