God has always wanted humans to "be perfect", if by that we mean without sin. We have always failed at this, and God has always gotten angry. This starts in Eden, and even Jesus told us to "be perfect" (e.g. see Sermon on the Mount), and was really upset at sinners _who did not want to change their ways_.
Romans 3: "... for all have sinned and fall short of the glory of God." Yeah, it's humanly impossible not to sin.
It is crucial to Christianity that humans are saved "freely by his grace through the redemption that is in Christ Jesus" (Rom 3), "and this is not from yourselves, it is the gift of God" (Eph 2).
