Between 1949 and 1952, American neuroscientist Paul D. MacLean developed and refined what became known as limbic system theory, building on James W. Papez’s earlier proposal of an “emotional circuit” (Papez, 1937) to argue that a set of interconnected midline brain structures, including the hippocampus, amygdala, cingulate gyrus, and hypothalamus, form a functional system mediating emotion, motivation, memory, and social attachment (MacLean, 1949, 1952). MacLean later popularised this work within his broader “triune brain” model, distinguishing reptilian, paleomammalian (limbic), and neomammalian (neocortical) functions. From a Christian and theological perspective, limbic system theory resonates with the Biblical view of the human person as an integrated unity of heart, mind, and body rather than a disembodied intellect alone: Scripture consistently locates emotions, moral discernment, and relationality in the “heart” (lēb), as in Proverbs 4:23 (“Above all else, guard your heart, for everything you do flows from it”) and Psalm 42:5, while affirming that embodied processes participate in spiritual life (Romans 12:1–2; Mark 12:30). Rather than reducing humanity to biology, MacLean’s work can be read as illuminating the created means through which God designed humans to love, fear, remember, bond, repent, and flourish in community (Genesis 2:7; 1 Thessalonians 5:23). For personal wellbeing, understanding the limbic system clarifies why emotional regulation, secure attachment, and memory integration are central to mental health, spiritual formation, and practices such as prayer, confession, and forgiveness (Philippians 4:6–7), while at a societal level it underscores how empathy, moral emotions, and social bonds are biologically grounded capacities that can be cultivated or damaged by cultural structures, informing education, justice, and public health in ways that promote peace and compassion (Micah 6:8; Matthew 22:39).