The same applies for doing bad things, your motives shouldn't be to not be punished, but to act rightly
An extension of this, Could you be blamed for the things you do when you're under duress? If I pointed a gun to your head and made you do something wrong, are you to blame?
The threat of hell (And the reward of heaven) might just be a different kind of gun, you might not be to blame for the wrong, but then you're also not the source of the good either, you're just acting on your own selfish interest
What a world
I would recommend instead something relevant to modern life and devoid of mysticism and muddy thinking: https://en.wikipedia.org/wiki/The_Demon-Haunted_World
The Bible is against slavery. See Philemon. Sinning until the last moment doesn't count unless it's a true heart change. See Ezekiel. Treating it as a Get Out Of Hell Free card would not fly.
Were you able to type this with a straight face?