The root of all sin is a lack of thankfulness (Romans 1:21).
The refusal to notice, name, and give thanks for the innumerable gifts and blessings that come with life in the creation is a form of insanity, both in how it develops naïve entitlement in us and in how it disregards the gracious and creative work of God Almighty, even in the midst of a disordered and rebellious world, as nothing.
It is no accident that the Apostle Paul begins his most thorough assault on humanity’s sinfulness (Romans 1:21-32) by drawing attention to humanity’s thankless disregard for the Wonderful Creator and his Full-Of-Wonder Creation.
Thus, fighting for thankfulness by regularly and actively seeking out evidences and instances of blessing and grace is the preeminent heart-level work we need to engage in if we are to fight against sin.
The practice of thankfulness is the most important spiritual discipline.