[julioademar]

Proof of work is not a consensus model, it's a method to elect a block author, an incentive mechanism designed to keep miners honest.

Consensus is the process through which the network agrees on state. Examples are Nakamoto consensus (e.g. Bitcoin), BFT (e.g. Tendermind) or GRANDPA+BABE (Polkadot).

[littlestymaar]

I think the GP meant: “the security comes from a consensus, not from proof of work”.