Murder is always wrong. But, because it means unlawful killing, there can be killing that is lawful, as in death penalty, which is not the same as murder. And I think death penalty is not necessary wrong, because I don't think it would be good to allow evil to continue eternally. However, I think that decision should be left for God, not for people.Unless god commands you to do it, then it's a-ok. In other words, your morality depends on the whim of some god, depending on what kind of mood it's in today.
Where is that said in the Bible? By what I know, eternal life is promised only for righteous:He supposedly promised eternal life for those who believe and worship and praise him endlessly.
And these shall go away into everlasting punishment, but the righteous into everlasting life.
Matt. 25:46
And I think it is good, if unrighteous and evil people don't get that, because, if they would live eternally, they would make life eternal suffering for all.