The parallel (but in the opposite direction) with the New, potentially peacefuler(1) Testament replacing the older, bloodier one, in Islam is that the "newer" Quran verses (and in the same book specifically proclaimed to be "more true" even if "all are true") are actually those calling for Jihad and the "unbelievers" (original: Kafirs https://en.wikipedia.org/wiki/Kafir or mushriks, depending on the verse) to be "slayed" (and variants). The original term for the "newer verses are more true" principle (also known as abrogation) is:
https://en.wikipedia.org/wiki/Naskh_(tafsir)
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1) but still, regretfully, threatening with the "hell" for ever and ever for the "sinners," judgement day and the stuff