Jabir(ra)related that Rasulullah(saw) had asked for the leftovers of food on the plate and those stuck on the fingers to be cleaned while saying, "You do not know which part of your food that carries the blessings."
It is bad to have leftovers when eating as those leftover food are part of God's gift to us. Make it a habit not to have any leftover even of the slightest bit. If we are quite full in the first place, do not take the food in excess. Always try to finish those food which are left on the plate and those stuck on our fingers. Maybe those leftovers are the ones that carry the blessing.
Remember this, while we eat...More than 1 billion people in this world are chronically starving and malnourished. Family and friends, let us be grateful and thankful for what we have.
This photos really made me cry. And it broke my heart. SPEECHLESS.