You have noticed that the habit of most lecturers and worldly orientated Muslims, is to praise wealthy people and those of high status. They compose odes in their praise. There are six harms of flattery, four for the one who flatters, and two for the one who is addressed. As for the one who is flattering, the harms are:
a) he mentions such things that are contrary to the reality, which are open lies and a major sin.
b) he expresses such love which he does not possess in his heart, thus he is guilty of hypocrisy and boasting.
c) he utters that which he has not established, based on mere conjecture e.g. he states, “Verily he is very pious, he is just.” Once Rasulullah Sallallahu Alaihi Wa Sallam said, ” If you have to praise anyone, then say, I think so-and-so is like this,” since it is not permissible to regard assumptions as facts.
d) if an oppressor or open sinner is praised due to which he becomes pleased, then the one who praises will be committing a sin by pleasing him, Rasulullah Sallallahu Alaihi Wa Sallam said, “Verily Allah (Ta’laa) becomes angry when a sinner is praised.”
Hasan Radhiyallahu Anhu said, “Whoever supplicates for long life for a sinner, he is pleased that Allah (Ta’laa) is disobeyed.”
An oppressor and sinner should not be praised, but admonished in order for him to leave his oppression and sin.
The harms for the one who is being praised are:
i) It results in pride and vanity, both of which are destructive. It is for this reason that when a person praised his companion before Rasulullah Sallallahu Alaihi Wa Sallam, Rasulullah Sallallahu Alaihi Wa Sallam said, “You have cut the neck of your companion.”
ii) He will hear his praises and become puffed up with pride, and this will result in laziness and negligence with regards to good deeds. A hadith sharif states, ” It is better for a person to slaughter his brother with a blunt knife, than to praise him in person.” The reason is that by being killed, one’s worldly life is destroyed, whereas the destructive ailments mentioned above, result in the everlasting life of the Hereafter being destroyed. However, if a person is saved from these harms, then there is no harm in praising that person. In fact, at times, it is mustahab (commendable) and a means of attaining reward. Rasulullah Sallallahu Alaihi Wa Sallam said, ” If the Imaan of Abu Bakr (Radhiyallahu Anhu) is weighed against the weight of all mankind (excluding Ambiya Alaihimus Salaam), his Imaan will be weightier”
Similarly, Rasulullah Sallallahu Alaihi Wa Sallam said, ” O Umar (Radhiyallahu Anhu)! If I had not been sent, you would have been sent.” Similarly, Rasulullah Sallallahu Alaihi Wa Sallam praised many of the Sahabah Radhiyallahu Anhum, since he knew that this would increase their enthusiasm, and would not result in ujub (vanity) in them.