I recently read an argument from a very wealthy person on how they had no more responsibility to help the poor than anyone else. Many interesting arguments have been written against responsibility of this or that type in recent days.
Christianity cuts to the core of the issue. The human heart is bad. Many arguments crafted by great intellectuals fail at this point. The motive is bad.
If we are not required to help others than we don't want to. You see this is the complete opposite of the intent of God.
God calls mankind into faith with himself and then asks that they seek to bless the world. God does not intend for mankind to sit and ask if inaction is permissible.
Christian love seeks what is right, loving, and true. It does not sit and ask is it ethically permissible to do nothing?
God cuts to the bottom of our human condition. We are to like Jesus who actively sought to help those in need at each moment. The question for the Christian is how we express love actively in the world, not whether it is ethical to do nothing.