How Can Christ's Work Atone for More than One Person?

After all, if Jesus was a single person, and only died and rose again once, shouldn't his saving work only be vicariously transferable to one other single person, if justice is to be maintained?

No, says Herman Bavinck--

When the Socinians say that . . . Christ could make satisfaction only for one person and not for many, inasmuch as he only bore the punishment of sin once, this reasoning is based on the same quantitative calculation as the 'acceptation' of Duns Scotus and the 'superabundance' of Aquinas.

For though the sin that entered the world through Adam manifests itself in an incalculable series of sinful thoughts, words, and deeds, and though the wrath of God is felt individually by every guilty member of the human race, it is and remains the one indivisible law that has been violated, the one indivisible wrath of God that has been ignited against the sin of the whole human race, the one indivisible righteousness of God that has been offended by sin, the one unchangeable eternal God who has been affronted by sin.

The punishment of Christ, therefore, is also one: one that balances in intensity and quality the sin and guilt of the whole human race. . . . That punishment, after all, was laid on him who was not an individual on a level with other individuals but the second Adam head of the human race, both Son of Man and Son of God.

--Herman Bavinck, Reformed Dogmatics, 3:402