Also from the authentic ahaadeeth.
Reported 'Aa.ishah (radhi-yallaahu 'anhaa): "Umm Salamah mentioned to Allaah's Messenger (sal-Allaahu alayhe wa sallam) that in Abyssinia she saw a church full of pictures and statues. He (sal-Allaahualayhe wa sallam) said:
((When a righteous man or pious worshipper among them dies they build a place of worship over his grave and set up all kinds of pictures and statues. They are the worst of all creatures before Allaah. They combine two evils; worshipping at the graves and making graven images and statues)), [Reported by Bukhaaree and Muslim].
Also in al-Bukhaaree and Muslim it is reported that 'Aa.ishah (radhi-yallaahu 'anhaa) narrated: "When the death approached Allaah's Messenger (sal-Allaahu alayhe wa sallam) he began to draw a piece of cloth (bed sheet) over his face, (sometimes covering and sometimes removing because of distress), he (sal-Allaahualayhe wa sallam) said in this state:
((Allaah's curse be upon the Jews and Christians for taking the graves of their Prophets as places of worship)), thus he (sal-Allaahu `alayhe wa sallam) warned the people about their actions."
Muslim reported from Jundub bin 'Abdullaah (radhi-yallaahu 'anhu) who narrated: I heard the Prophet (sal-Allaahu `alayhe wa sallam) say only five days before his death:
((I am free and clear towards Allaah of having any of you as my Khaleel (specially close friend). Verily, Allaah has taken me as His Khaleel just as He had taken Ibraaheem (`alayhis-salaam) as a Khaleel. If I would have taken anyone from my Ummah as a Khaleel, I would have taken Abu Bakar (radhi-yallaahu 'anhu) as a Khaleel. Beware! those who preceded before you, used to make their Prophet's graves into places of worship. Beware! Don't take (any) graves as places of worship. I forbid you to do so))
He (sal-Allaahu `alayhe wa sallam) forbade this at the end of his life. After this (forbidding of taking graves as place of worship), he cursed anyone who did such deed within this context.
Imaam Abu Haneefah said:
((It is not befitting for anyone to call upon Him, except by Him, and with the supplication that He has permitted and commanded, that which is instructed in His statement:
{And Allaah has Beautiful Names, so call upon Him by them, and leave the company of those who deviate concerning His Names. They will be recompensed for what they used to do})), [Soorah al-A'raaf, Aayah 180], [ad-Durrul-Mukhtaar ma'a Haashiyah Raddul-Mukhtaar (6/396-397)]