[luncheonmeat]

God decree punishment in this world to stop others doing it.

As per your logic can  we forgive our minister?give him a second chance?

In Sinpwn, if the ministars broke the law of the land, they will be required to undergo the sentencing. Ask Iswaran. 
In bolehland, it would depend on how powerful the ministar is. Ask Najib. 
Whether you want to give the incumbent another shot at running the country is up to the individual. This has nothing to do with 'forgiveness', unless they have somehow sinned against you, in which case, you would be considering whether to bor mata, not whether to vote for him. 

During the time before Christ, only God could forgive sinners for breaking his laws [of course there was still the matter of making offerings for their offences].

During Jesus' time, the Jewish authorities were scandalised and accused Jesus of blasphemy when he forgave the sins of the repentent since no one had this power except God. Who and what gave Jesus the power to forgive sinners? Ans. God who had sent Jesus to die for our sins.
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