Apparently there is no authentic statement to suggest that the Prophet held the Qul ceremony on the third, tenth or fortieth day of the death of a person. Is there any harm in holding such a function, particularly since it encourages people to do something highly recommended, i.e. reading the Qur'an.
On an authentic Hadith, Lady Aisha quotes the Prophet as saying: "He who innovates something in the matter of ours (i.e. our religion) that is not of it will have it rejected." (related by Al-Bukhari and Muslim). You started your question by saying that there is apparently no authentic statement or report to support this ceremony you name as "Qul". Hence, it must not be practiced, particularly since it is of a religious nature. We rely on the Prophet for explaining to us what is part of our faith and what is not. He has conveyed to us Allah's message complete.
Therefore, any addition, even though it may have a religious appearance, must be rejected. The point is that if that addition is part of Islam, then why has the Prophet not explained it. Since the Prophet has given us our religion complete, then how can we add to what he has given us?
You say that it encourages people to do something good. Yes, but it also has the great disadvantage of inventing something the Prophet has not mentioned. If people will not read the Qur'an normally, then their reading of the Qur'an on these occasions does not give them the habit of reading it. It is indeed of little benefit to them or to others. We should always confine ourselves to what the Prophet has taught us. We accept no addition and no omission.
• Qur'an: A surah not to be read frequently
An old man told me that one should not recite the surah entitled "A'bas" or "The frowning" very often. He gives the reason saying that the surah contains a reproach to the Prophet for having frowned on a blind man who came to him to seek guidance. Please comment.
It is true that the surah you have mentioned tackles the incident when a blind man, a companion of the Prophet, came to him requesting that the Prophet teach him a passage of the Qur'an. At the time, the Prophet was speaking to a few people who commanded high position in Makkah. The Prophet had high hopes to win them over to Islam. He felt that if they gave him a positive response, Islam would become much stronger in Makkah. Therefore, he wanted to devote all his attention to them at that time. The blind man, however, pressed his request time after time. The Prophet did not like that, but he did not express his displeasure in any words. He simply frowned, obviously unnoticed by the blind man. Allah then revealed this surah telling the Prophet that his attitude was not the right one. It was not up to him to make people follow divine guidance. It is Allah who guides whomsoever He pleases to the right path. The surah contains a strong reproach telling the Prophet [that] he could not refuse to teach anyone who sought to be taught. No person of high position is to be preferred to a humble person.
To suggest that this surah should not be read often may be motivated by a noble feeling. A person may feel that he does not wish to read the reproach to the Prophet often. This feeling, however, is mistaken because it misses out on the lesson to be learned and concentrates on appearances and superficial elements. The message of the surah is one of the essential elements of the Islamic faith. All people are equal and all deserve to be called upon to believe in Allah and His messenger. None is to be preferred on account of his high position. None is to be ignored on account of his humbleness. That Allah has chosen to give this very important principle in the way He has, making use of the incident I had just described in order to drive the point home is His own prerogative. We read this surah in the same way as we read other parts of the Qur'an. Every portion is highly relevant and highly important. We cannot ignore any part of it for any consideration whatsoever.
The old man who told you not to read this surah often might have spoken out of love for the Prophet. We should remember, however, that no matter how dearly we love the Prophet, Allah loves him more. If we were to ignore this surah our attitude represents a protest against its inclusion in the Qur'an. This is not up to us to do. Every part of the Qur'an is as important as the rest. The old man is mistaken and we treat this surah in the same way as we treat the other 113 surahs.
• Qur'an: Abandoning the Qur'an
When Muslims broke their covenants with their Lord and abandoned the Qur'an, they suffered the set backs and calamities known to everyone. It is true that they continue to be enhanced with musical recitations of the Qur'an and may use it as charms, but this is not the purpose for which the Qur'an was revealed. Indeed, when the Qur'an is not implemented in the lives of the Muslim community, it is effectively abandoned by it, regardless of how much lip service is paid to it.