In what sense are the people in Romans 1 haters of God?
They are haters of God inwardly, not necessarily openly marching with placards, because they know they are in opposition to what God wants them to do. Though they know God's judgment and that such things are worthy of death, they still do them and approve others who do them.
Les explains that these people are called haters of God. They may not openly march with placards saying they hate God, but down deep in their heart they do, because they know they are in opposition to what He wants them to do. The context lists their traits: filled with all unrighteousness, fornication, wickedness, covetousness, maliciousness, envy, murder, debate, deceit, malignity, whisperers, backbiters, haters, disobedient to parents, without understanding, covenant breakers, without natural affection, implacable, and unmerciful. They know the judgment of God, that those who commit such things are worthy of death, yet they not only do the same but have pleasure in those who do them—they applaud and cheer them on.
Backbiters, haters of God, despiteful, proud, boasters, inventors of evil things, disobedient to parents,