Reference: http://mufti.af.org.sa/ar/content/ما-هو-التعظيم-الحقيقي-للنبي-صلى-الله-عليه-وسلم
Question: They say they want to venerate the Messenger of Allaah (sal-Allaahu ‘alayhi wa sallam); so how is true veneration of the Messenger of Allaah (sal-Allaahu ‘alayhi wa sallam) to be done?
Response: True veneration of the Messenger of Allaah (sal-Allaahu ‘alayhi wa sallam) [starts with] complete belief in him, and adhering to his legislation, and ruling in accordance with it.
Allaah (Subhaanahu wa Ta’aala) said:
And the Prophet (sal-Allaahu ‘alayhi wa sallam) said:
The one who loves him venerates his Sunnah by acting in accordance to it, and gives preference to his speech over and above all of the people. [So] whoever holds fast to the Sunnah – acting in accordance to it and steadfast upon it in his prayer, his zakaah, his fasting, his hajj, and his treatment of his parents, relations, neighbours and brothers – then he is firm upon the Sunnah, of love for it – having placed Muhammad (sal-Allaahu ‘alayhi wa sallam) his example [to follow] and his imaam; as Allaah (‘Azza wa Jall) said:
As for those who commit shirk with Allaah, and detract their worship away from him calling for the alleviation of harm, the attainment of benefit, and the seeking of intercession – then these [people] do not love the Prophet (sal-Allaahu ‘alayhi wa sallam); they are instead his enemies because he (sal-Allaahu ‘alayhi wa sallam) was sent [as a prophet] to combat shirk, and prohibit it [as Allaah (‘Azza wa Jall) said]:
And the Messenger (sal-Allaahu ‘alayhi wa sallam) warned us against building graves, and towards the end of his life he said:
And the Prophet (sal-Allaahu ‘alayhi wa sallam) said: