(Exodus 31:15) "Six days will work be done." And a different verse (Ibid. 20:9) "six days shall you work, and you shall do all of your work." How are these two verses to be reconciled? — When Israel do the L–rd's will, their work will be done by others, viz. "will work be done." And thus is it written (Isaiah 61:8) "And strangers will arise and graze your sheep, and the sons of strangers, your farmers and your vintners."
When Israel Does God's Will, Their Work Is Done by Others
Mekhilta Tractate Shabbata 1:21