“This is what everyone who is entered in the records shall pay: a half-shekel by the sanctuary weight to “atone for your souls.” (Exodus 30:13)
The Tosafot surmises that
"Moses was perplexed, thinking to himself, 'What can a person possibly give that will serve as atonement for his soul?' Thereupon, God showed him a 'coin of fire.'"
Question - How can a "coin of fire" grant atonement for one's soul?
Rabbi Menachem Schneerson answered with a parable:
A person once served as an apprentice to a silver and goldsmith. The artisan taught his apprentice all the necessary details except for one, which he omitted because of its utter simplicity: in order to melt gold and silver and change its shape, a fire must be lit under the metals.
Setting out on his own, the apprentice faithfully followed all the particulars his master taught him, leaving out that one "minor" detail that his teacher had omitted, the need for a fire. Because of this omission, of course, nothing happened. The silver and gold remained as they were, and the apprentice could fashion nothing at all.
God similarly responded to Moses by showing him a ‘coin of fire,’ (the half-shekel). (Likkuti Sichos, Vol. III, pages 923-28; from Parashat Shekalim - "An Undivided Half-Shekel")
The parable explains that merely offering a half-shekel coin doesn't bring about atonement. But, when the coin is offered with fire, referring to soul-fire, then the half-shekel atones even for a sin as grievous as the sin of the Golden Calf.
Another question - Why does Torah ask for only a half-shekel and not a whole shekel?
Rabbi Levi Yitzhak of Berditchev explains in a complex Kabbalistic discussion (Kedushat Levi, vol. 2, p 494, Lambda Press) that what we’re dealing with here are purely spiritual matters, that when an Israelite gives a half-shekel of twenty gerah weight, it isn’t about the monetary value we earthly beings require to physically sustain a community. Rather, it’s about how we may enter into God’s presence.
The first letter in the word Keter (Crown - the highest emanation of God on the Kabbalist chart of emanations) is chaf, and chaf equals twenty according to Hebrew letter-number equivalents, the same as the weight of the half-shekel, thereby indicating that the 20 gerah (chaf-Keter) weight half-shekel is a spiritual metaphor of ascent towards yihud (unity) with God at the highest level.
Rabbi Levi Yitzhak explains that without the spiritual fire no offering, no gift, no presentation from the heart will succeed in linking heaven and earth. Soul-fire is the critical element that enables yihud, union, between us and God.
It is part of the human condition that we are broken, flawed, distracted, seducible, unfocused, fragmented, disloyal, weak, and imperfect. The golden calf incident is the most spectacular example in the Biblical period of betrayal perpetrated by the people against God. Only 39 days before the making of the golden calf (in this week's Torah reading) they heard the commandment against worshipping false gods, and they made the object and celebrated it as a god in spite of what they had only recently experienced at the foot of Mount Sinai.
Those who had turned away from God badly needed a means to return to holiness. Restoration, thankfully, is always possible. Rabbi Simon Jacobson writes that "Moses offers us a rare - once in history - glimpse into the intimate secret of communicating with the Divine, as he beseeches God to forgive and reconcile with the people.... Moses implores God, ‘Show me Your face.’ [And in response] God forgives.”
Mending our relationship with God (and with those we love and community) is a fundamentally restorative and healing process, and it begins with the offering of the half-shekel.
Judaism teaches that we are most whole when we enter into authentic, trusting, loyal, loving, and passionately committed relationships with family and friends, with a sacred community and with God. That is the lesson of the half-shekel "coin of fire."
For those of us who do not believe there is a God or, at the very least are skeptical about ever experiencing a relationship with the Divine, then I suggest that you let authentic relationships with loved ones and with community suffice. Perhaps the Divine-human experience will follow.
Our Torah portion and the Midrashic literature teach that the ‘coin of fire,’ the half-shekel, facilitates atonement (read instead "at-one-ment"). When that occurs, when we offer a coin of fire we become, in effect, God’s light, as it says in Proverbs (20:27) - Nishmat adam ner Adonai - “The human soul is the lamp of God.”