Discerning Between Truth and Error

Are you able to differentiate between truth and error, light and darkness, the spirit of the Lord and the spirit of this world? We are living in difficult times in which the lines have been blurred more than ever, requiring more reliance on God than ever before. Jesus prayed for us, "Sanctify them through thy truth: thy word is truth." (John 17:17). 
As deception grows more prevalent, may the Lord do so in these last days.