Matt 15:14 And Sins Committed In Ignorance

Matthew 15:14 reads "… if the blind lead the blind, both shall fall into the ditch."What happens according to this verse to a Christian who sins in ignorance by blindly following a false teacher? Does he make it across the road because he is "sincere?" No, he falls into the ditch (spiritual condemnation).We can sure apply Prov 14:12 and Matt 15:14 to the denominations, but what about applying them to ourselves?