One candle giving off light

The picture above was posted to the Prime Minister's Facebook page on Saturday night. The following message went with it (Hat Tip: Leah P).

I
recall something the Lubavitcher Rebbe told me when I went to the UN.
He told me: 'Remember that even when you are in a world that is all dark
and you light one candle, one candle of truth, the light – the precious
light that this candle gives off,