Forsaking those which are transitory, betake thyself to that which is everlasting, and let contentment be thine, for contentment is the highest of all acquisitions. Behold, illustrious and mighty kings, having ruled lands abounding with wealth and corn, have become the victims of the Universal Destroyer, leaving behind their kingdoms and vast sources of enjoyment. The son brought up with anxious care, when dead, is taken up and carried away by men (to the burning ground).

In plain words: Vidura says to let go of things that don't last, hold on to what does, and be content, because contentment is the greatest thing you can gain. Even great, rich kings die and leave everything behind. Even a son raised with loving care is carried to the cremation ground when he dies.