A Christian complains about prohibition of Muslims
    celebrating or congratulating people at Christmas
Question

                Why do you condemn the celebration of the
      what Christians think is birth of the son of God (Allah)? We should be teaching respect
      for other peoples and religions. Yet with such condemnation and calling it falsehood, it
      makes it difficult for rational, honest, and respectful persons to communicate.
Praise be to Allah.Praise be to the One God, who begets not, nor is 
  begotten. 
You seem to have misinterpreted the condemnation 
  of celebration of Christmas as a matter of disrespect for Christians. In reality, 
  it is out of respect for Allah and Jesus and the teachings of our Prophet Muhammad, 
  peace be upon them. It is an integral part of our faith to reject celebrations 
  that have not been prescribed and/or that have a basis in falsehood, as inevitably 
  they lead to misguidance and alterations in faith, as has happened with Christianity. 
  There is nothing "radical" or "fringe" about this. It is 
  our basic right to protect our faith and practice from distortion and falsehood. 
  Surely no one has a right to condemn us for this. 
Do you think Encyclopedia Britannica is rational 
  and honest? Please read what they have to say about Christmas: 
Excerpts quoted directly from http://www.britannica.com 
  : 
The word Christmas is derived from the Old English 
  Cristes maesse, "Christ's Mass." : 
( There is 
  no certain tradition of the date of Christ's birth. Christian chronographers 
  of the 3rd century believed that the creation of the world took place at the 
  spring equinox, then reckoned as March 25; hence the new creation in the incarnation 
  (i.e., the conception) and death of Christ must therefore have occurred 
  on the same day, with his birth following nine months later at the winter solstice, 
  December 25).
...
According to a Roman almanac, the Christian festival 
  of Christmas was celebrated in Rome by AD 336...
 ( The reason why Christmas came 
  to be celebrated on December 25 remains uncertain, but most probably the reason 
  is that early Christians wished the date to coincide with the pagan Roman festival 
  marking the "birthday of the unconquered sun" ) (natalis solis 
  invicti); this festival celebrated the winter 
  solstice, when the days again begin to lengthen and the sun begins to climb 
  higher in the sky. The traditional customs connected with Christmas have accordingly 
  developed from several sources as a result of the coincidence of the celebration 
  of the birth of Christ with the pagan agricultural and solar observances at 
  midwinter. In the Roman world the Saturnalia 
  (December 17) was a time of merrymaking and exchange of gifts. December 25 was 
  also regarded as the birth date of the Iranian mystery god Mithra, the Sun of 
  Righteousness. On the Roman New Year (January 1), houses were decorated with 
  greenery and lights, and gifts were given to children and the poor. To these 
  observances were added the http://www.britannica.com/bcom/eb/article/idxref/0/0,5716,266282,00.htmlGerman 
  and Celtic 
  Yule rites when the Teutonic tribes penetrated into Gaul, Britain, and central 
  Europe. Food and good fellowship, the Yule log and Yule cakes, greenery and 
  fir trees, and gifts and greetings all commemorated different aspects of this 
  festive season. Fires and lights, symbols of warmth and lasting life, have always 
  been associated with the winter festival, both pagan and Christian. Since the 
  European Middle Ages, evergreens, as symbols of survival, have been associated 
  with Christmas...  [end quote] 
So as any rational person can see, there is no 
  sound basis for Christmas, nor did Jesus (peace be upon him) or his true followers 
  celebrate Christmas or ask anyone to celebrate Christmas, nor was there any 
  record of anyone calling themselves Christians celebrating Christmas until several 
  hundred years after Jesus. So were the companions of Jesus more righteously 
  guided in not celebrating Christmas or are the people of today?
So if you want to respect Jesus, peace be upon 
  him, as Muslims do, don't celebrate some fabricated event that was chosen to 
  coincide with pagan festivals and copy pagan customs. Do you honestly think 
  God, or even Jesus himself, would approve or condemn such a thing? If you say 
  approve, then obviously you are not interested in the truth.
We ask Allaah, the One, Singular God, with no partners 
  or sons, the God of all creation and mankind, to guide us all to the path of 
  guidance and sincerity.