To the same extent as it is good to give thanks to Hashem and to sing praises and songs, so too on the other hand it is a great sin to sing songs of gentiles or songs of lightheadedness, and especially while drinking wine, as by doing this one is transgressing the verse “They may not drink wine with song!”. This is a sin even in the case that they think that they are doing it for a Mitzvah (e.g. to make a bride and groom happy).
If Hashem has favored someone with a pleasant voice, if he uses it to sing for a sinful activity, this person can be compared to someone who has been given a new set of clothes by the king so that the king will be proud of him when he comes before the king and instead this person dresses his dog in those clothes in which case it is obvious that the king will become very angry.
It is a very bad illness that there are many things which the public have trampled underfoot and they have become considered like they are completely permitted. These things include these forbidden songs, the prohibition to speak idle speech, the prohibition to miss even one free second from learning Torah etc. When a wise man will stand up and say that this is a great sin the listener will say “How much is this wise man imposing on us! Who can possibly keep his words? This is the habit of the entire world and whatever happens to them will happen to us!”. How good it would be if a soul could come back from the next world and relate the greatness and severity of the punishment for these sins. We can only rely on the support of our Father in heaven that He with His great compassion will plant in the hearts of His nation Klal Yisrael the love and fear of Him to make the nation’s wishes like His own and to listen to the words of wise men for their own good. Amen so shall it be.

