Latest / Matmonim: Daf Yomi by Rabbi David Lapin
Bechorot 43a Preserving Chosenness - קדושתן מרובה
Chosenness applies not only to the sacrifices we bring (מבחר נדריכם) and the mitzvot we do מצוות מן המובחר)). Yisrael itself was chosen. However once chosen, chosenness needs to be preserved or it can be lost. Shmirat hamitzvot preserves Jewish chosenness, Jewish sanctity.
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