This touches on a deeper issue: What did God originally call "very good" (Genesis 1:31), and how has sin affected the natural world? Parasites—organisms that live on or in another organism at the host's expense—can cause immense suffering. Are parasites considered good in God’s eyes? And if God promises a renewed creation, what will become of them?
The question assumes one of two possibilities: either (1) God created parasites exactly as they are today, or (2) parasites arose only after the Fall. Scripture does not explicitly answer which is correct, so Christians should hold their conclusions. What Scripture does clearly teach is that God is the Creator of all living things (Genesis 1–2; Psalm 104), that creation was originally "very good" (Genesis 1:31), that human sin brought corruption into creation (Genesis 3; Romans 8:20–22), and that Christ will ultimately renew all creation (Colossians 1:20; Revelation 21–22).
There are several faithful Christian perspectives on parasites.
The first is that God created the ancestors of today's parasites with a different ecological role. Some scientists and theologians have suggested that organisms now known as parasites may originally have been free-living or engaged in harmless relationships with other species. Following humanity's rebellion, creation became subject to "futility" (Romans 8:20), and these organisms adapted into harmful lifestyles within a now-corrupted world. This view fits well with Paul's description that "the whole creation has been groaning together in the pains of childbirth until now" (Romans 8:22, ESV). It sees parasitism not as God's original intention, but as one expression of creation's brokenness.
A second view is that parasites were always part of God's good design, serving important ecological purposes such as regulating populations, maintaining biodiversity, and preventing particular species from dominating ecosystems. Modern ecology shows that parasites are remarkably abundant—perhaps constituting around half of all known animal species—and play significant roles in food webs, nutrient cycling, and ecosystem stability. Some parasitologists even describe parasites as "ecosystem engineers." From this perspective, the problem is not necessarily the existence of parasites themselves, but the suffering associated with them in a fallen world.
Either way, Christians should remember that Scripture's definition of "good" is broader than merely "comfortable." God's creation included cycles, limits, dependence, and mortality for plants before the Fall, and many ecological relationships are complex. At the same time, Scripture never portrays disease, decay, and suffering as ultimate goods to be celebrated. They belong to the present age of groaning that awaits redemption.
What, then, about the new creation?
Isaiah's vision of the restored creation describes harmony replacing violence:
"The wolf shall dwell with the lamb... They shall not hurt or destroy in all my holy mountain" (Isaiah 11:6–9, ESV).
Similarly, Revelation promises that "death shall be no more, neither shall there be mourning, nor crying, nor pain anymore" (Revelation 21:4, ESV). While these passages do not specifically mention parasites, they point toward a world where suffering, disease, and death no longer exist.
This does not necessarily mean that every organism we currently call a parasite will cease to exist. Rather, if parasites are present in the renewed creation, Christians can reasonably expect them to exist in ways fully consistent with God's perfect peace and flourishing. Their biology or ecological function may be transformed so that they no longer inflict harm. Just as resurrected human bodies are continuous with our present bodies yet gloriously transformed (1 Corinthians 15:42–49), creation itself will experience renewal rather than annihilation (Romans 8:21).
Ultimately, the Bible invites us to place greater hope not in answering every biological question, but in trusting God's promise that "the creation itself will be set free from its bondage to corruption and obtain the freedom of the glory of the children of God" (Romans 8:21, ESV).
This question also reminds us that creation care is not based on believing the world is already perfect. Rather, Christians care for creation because it still belongs to God (Psalm 24:1), bears witness to His wisdom (Psalm 104), and is destined for redemption through Christ (Colossians 1:15–20). Even as we encounter disease, invasive species, parasites, and ecological disruption, we participate in God's work of anticipating His coming kingdom by protecting habitats, reducing unnecessary harm, and caring for both people and the rest of creation.
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