How to render Twig template from database in symfony2
I'm working on application written in symfony2 and I want to send email after some action/event... the problem is, that users can definig something like "email templates" which stores in db like simple string, for example: "This is some email from {{ user }}" and I need to render body for email from that template... 
In symfony documentation from this link: http://symfony.com/doc/2.0/cookbook/email.html#sending-emails the methos for render is $this->renderView and it expects reference to file as "bundle:controller:file.html.twig", but my template is database as simple string...
How can I render it?
How to render Twig template from database in symfony2
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I'm working on application written in symfony2 and I want to send email after some action/event... the problem is, that users can definig something like "email templates" which stores in db like simple string, for example: "This is some email from {{ user }}" and I need to render body for email from that template... 
In symfony documentation from this link: http://symfony.com/doc/2.0/cookbook/email.html#sending-emails the methos for render is $this->renderView and it expects reference to file as "bundle:controller:file.html.twig", but my template is database as simple string...
How can I render it?