The problem with false teaching is that some aspects of it have truth, which then can be used improperly. It is true that God knows about our generosity and can reward believers for their faithfulness. Sometimes this is overemphasized and used as a manipulation tactic to prompt people to be generous with a (their) specific ministry. I think it is relevant to teach the whole counsel of God’s Word including this passage but I would be wary to respond to a teacher who seems to use this in an overly persuasive, pressurized manner to compel people to give to them.