But what is the ring?
The ring is power..the power to rule, to dominate, to fullfill your own will, and impose it on others.
The Hobbits are common men, who seek only simple pleasures and help each others.
When Frodo "inherits" the ring, it is understood by the great that even though he is not a "great" or powerful person, that he has qualities that are more important, and that he, not "an elf warrior" needs to destroy it.There is a passage where Gandalf says Frodo was "meant" to find the ring...the implication is that God arranged this "coincidence"...
Frodo has qualities that include humility and weakness: he has no desire to rule others. And he accepts the burden, understanding that this is his task...If the wizard or others took the ring, they would be tempted since they are people of power, and recognize the danger of power to corrupt: the danger to use power to "do good"...but leading to terror..
The christian theme here is that the meek will inherit the earth. The greatest Christian saints are often "nobodies"...like a little Albanian nun teaching rich girls in a school in India who decides to teach poor people...or a little cloistered nun in Alabama who decides to write books, then give a talk on Christian TV station, then to start a Catholic network...or a merchant's son and playboy who decides to rebuild a church and live poorly, and revives the church (st Francis)..or millions of other "nobodies" who do not seek power but allow God to use them as instruments..