Chapter Four: This is the concept of “And you shall command - tetzaveh”, which the word ‘tzivu - commandment’ also means ‘tzavsa v’chibur - to connect’. And when the Moses of Each Generation (“And you shall”) connects the Children of Israel with G-d, then, “and they shall take to you pure olive oil”, that Israel, through their service of Torah and Mitzvot, will add in the revelation of Light within Moses, and then it will be that Moses’ Candle will be “the candle (lights of the Temple’s Menorah being burning) perpetually” (and not just “from evening to morning”).
To understand this, the Previous Rebbe explains that Moses is called the Faithful Shepherd, which can also be translated as the Shepherd of Faith, that Moses (including the Moses of Each Generation) feed the Children of Israel Faith, that Israel can then serve G-d with self-sacrifice.