There is No Purpose in Working on Shabbos & The Importance in Carefully Following the Its Halachos

From B'yam Darkecha on the Beauty of Shabbos & the Yomim Tovim: R Yossi Michalowicz by R Yossi Michalowicz.

pp. 379 - 385 : Understanding why there is no purpose in doing work on Shabbos. Physical acts of keeping the shabbos is the foundation of achieving Deveikus of the heart on Shabbos. The Poison of sinning kills any possibility of Deveikus. The far reaching destruction of the worlds that comes from sinning. The Moshol of the servant whom the king adjured not to make even a safe bet.