John Wesley on Romans 1:21

Because, knowing God - For the wiser heathens did know that there was one supreme God; yet from low and base considerations they conformed to the idolatry of the vulgar. They did not glorify him as God, neither were thankful - They neither thanked him for his benefits, nor glorified him for his divine perfection. But became vain - Like the idols they worshipped. In their reasonings - Various, uncertain, foolish. What a terrible instance have we of this in the writings of Lucretius! What vain reasonings, and how dark a heart, amidst so pompous professions of wisdom!