כָּל־הַמִּצְוָ֗ה אֲשֶׁ֨ר אָנֹכִ֧י מְצַוְּךָ֛ הַיּ֖וֹם תִּשְׁמְר֣וּן לַעֲשׂ֑וֹת לְמַ֨עַן תִּֽחְי֜וּן וּרְבִיתֶ֗ם וּבָאתֶם֙ וִֽירִשְׁתֶּ֣ם אֶת־הָאָ֔רֶץ אֲשֶׁר־נִשְׁבַּ֥ע יְהוָ֖ה לַאֲבֹתֵיכֶֽם׃
All the commandment which I command thee this day shall ye observe to do, that ye may live, and multiply, and go in and possess the land which the LORD swore unto your fathers.
Shenei Luchot HaBerit
כל המצוה אשר אנכי מצוך היום . Our sages in Bereshit Rabbah 60,2 advise that having commenced to perform a מצוה one should try to complete it. This is the message contained in our verse (11,8). It is only called a מצוה when performed in full.