Quotation for Moed Katan 25:2
ואם תמצי לומר מכר עבדו לעובד כוכבים ומת קנסו בנו אחריו משום דכל יומא מפקע ליה ממצות
Here, what do we say? That the Rabbis' intention was to penalize the man personally and he is no more, or, maybe that it was only to impose a pecuniary penalty [on his estate] and that is to be had? - R'Zera replied, You learned it [in the Mishnah]: 'A field that has been cleared of thorns<span class="x" onmousemove="('comment',' Merely picked up, cleared, lifted from the soil by the first superficial ploughing which did not constitute working the soil, forbidden Scripturally. vchhyb');"><sup>3</sup></span> during the seventh year may be sowed in the post-sabbatical year; if it had been well improved<span class="x" onmousemove="('comment',' By regular harrowing or deeper or cross ploughing. V. Tosaf. s.v. and commentary of R. Samson of Sens on M. Sheb. IV, 2.');"><sup>4</sup></span>