There's an idea among liberal Christians that Christ's demand to give to the poor cashes out to passing laws that mandate wealth redistribution - ie, telling the men with guns to start taking money from people through threat of violence and imprisonment. This is like regarding the admonition to get married if you wish to have sex as license for the government to order women to marry men who wish to have sex.
If a liberal Christian balks at the latter - if they regard that as a horrible idea that does not follow Christ's commands, because the willing consent of both parties is absolutely essential - then it's pretty easy to see where the demand for government redistribution of wealth falls apart, at least as a Christian ideal. The point of the command to give to the poor is not simply 'the poor need money, give it to them by any means necessary', just as the command for sexually eager men to marry doesn't mean 'men need to have sex, let's round up some women and force them into a marriage'. To view either command that way is spiritually and intellectually warped - and in large part, they stand and fall together.
This isn't to say that no justification for wealth redistribution can exist. It's to say that trying to interpret Christ's commands in that way fails, badly and obviously. When Christ tells people to give to the poor, the goal is not merely to change the economic state of the poor person, but to change the intellectual state of the wealthy person. Yes, I know - that's difficult, and they may not agree. Too bad. There is no shortcut here.