“It will be, because you heed these ordinances, and observe and perform them, that the Lord your God will maintain for you the covenant and the kindness regarding which He took an oath to your forefathers” (Deuteronomy 7:12). Halakha: If a person of Israel has a candelabrum made of separate pieces, may one carry it on Shabbat? So taught the Sages: One who assembles the branches of a candelabrum on Shabbat incurs liability to bring a sin offering.
For what is he liable? Rabbi Abbahu said in the name of Rabbi Yoḥanan: One who assembles the candelabrum on Shabbat is like one who builds on Shabbat, and one who builds on Shabbat is liable. Rabbi Yosei ben Rabbi Ḥanina said: When did Israel observe Shabbat properly? When it was first given to them in Alush.
From where is this derived? As it is stated: “The people rested on the seventh day” (Exodus 16:30). [God said:] ‘Do you perhaps think that I gave you Shabbat to your detriment? I gave it only for your benefit.’ How so?
Rabbi Ḥiyya ben Rabbi Abba said: [God said:] ‘You sanctify the Shabbat with food, drink, and clean garments, and bring pleasure to your soul, and I will give you reward.’ From where is this derived? “And you call Shabbat a delight…” (Isaiah 58:13). What is written thereafter?
“Then you will delight in the Lord” (Isaiah 58:14). “[Delight in the Lord], and He will grant you the desires of your heart” (Psalms 37:4). Israel said to Him: ‘When will you give us the reward for the mitzvot that we perform?’ The Holy One blessed be He said to them: ‘The mitzvot that you perform, their fruits you consume now, but their reward I will give you at the end [be’ekev].’1The word ekev literally means heel.
Just as the heel is the end of the body, the word ekev in this context implies the end of time (Etz Yosef). From where is this derived? From what we read in our verse: “It will be, because [ekev] you heed.”