[drstevej]

I think by "necessary" you mean "important."

If so, it is important in the debate over "free will" and "predestination."

No doubt subsequent posters may elaborate much more...

[JMJ333]

All advocates of predestination, from Lucidus to Calvin, have appealed to Augustine as their crown-witness, while Catholic theologians see in Augustine's teaching at most only a predestination to glory, with which the later "negative reprobation" to hell is parallel.

In actuality, Augustine is free from Calvin's idea that God positively predestined the damned to hell or to sin. The closest he might come to backing their theory is when he talked about "irresistable grace." The antithesis and the position of the words do not refer to the terms "inevitably and unconquerably" to the grace as such, they must be referred to the "human will" which, in spite of its infirmity, is, by grace, made "unyielding and unconquerable" against the temptation to sin.