Distinguishing between Rava’s lenient opinion and Abaye’s stringent opinion on liability to bring a sin-offering for certain unwitting violations of Shabbos. Opening Mishnah 2 of Chapter 7, the 39 forbidden labors of Shabbos. Why is sowing mentioned before plowing? A practical answer and a spiritual answer. One action can result in liability for violating multiple categories, and from this we may learn to work smarter not harder during the week. The labor must also be constructive rather than destructive, so we distinguish a hole dug for a foundation or planting vs. a hole dug for the dirt used to cover some filth.