Manipulator

1. To influence or manage shrewdly or deviously: He manipulated public opinion in his favor.
2. To tamper with or falsify for personal gain: tried to manipulate stock prices.

A word closely related to "spin". They couch their "argument" in empty or undefined phrases which try to leave their opposition in unwinnable positions. Manipulators can rarely see the vacuousness of their non-argument and are usually so immersed in their own wants as to be blind to alternatives.

Manipulative language, spin, seems essential to politicians, groups with a cause dear to them, advertisers and (because it is at least responding to these people) the media.

Popular amongst manipulators are phrases like, "if you loved me you would...". 
Well, of course you want to be loving. You certainly don't want to come across as unloving. What sort of a brute are you? So you try to explain why you will not do as requested - and in the process prove you "don't love me!" 
You might even try to say that refusing to comply does the manipulator more good than complying would - but manipulators are seldom convinced by that argument and it's likely to be a manipulative argument itself.
There are people who will dismiss or denounce religion, faith and Christianity in particular who are ready to explain what Christians should do and think.  They claim to know just what Jesus thinks on a subject and how he would react to the current circumstances. Clearly, if you don’t comply or agree then you cannot be  a “real Christian”.
This is also manipulation.  
It’s also offensive because they are speaking with ignorance and no authority, pretending to speak in Jesus’ behalf and even using his name to support their opinion.  They may be moving from being manipulative to being blasphemous.

Probably the best thing is to call the manipulation for what it is, reject the baseless claim and tell the manipulator to try to find a good, objective reason next time.

Then do something loving.