From a Sharî'ah point of view, it means "to perform acts which are pleasing to Allâh. with the intention of pleasing other than Allâh". The intention may be a totally false intention, where the person who does this act has no consciousness of Allâh whatsoever, or it may be a partially false intention, where the person does have Allâh in mind, but at the same time desires praise from other people.
From this definition, it can be seen that riyâ ' originates in the heart. The scholars of Ahlus Sunnah wal-Jamâ'ah are agreed that belief (îmân) comprises actions of the heart (such as fear, love, trust and hope), actions of the tongue (such as the utterance of the shahâdah), and actions of the limbs (such as the performance of the prayer and pilgrimage). Shaykh al-Islâm Ibn Taymîyah said. "[The actions of the heart] are part of the fundamentals of belief, and the foundations of religion. Included in it are: love for Allâh and His Messenger trust in Allâh, sincerity of religion for Allâh. thankfulness to Him, patience with His Decree, fear of Him. ... and all of these actions are obligatory upon all of the creation, according to the unanimous agreement of all the scholars." Ibn Qayyim al-Jawzîyah said. "The actions of the heart are the foundation (of belief), and the actions of the limbs follow and complete them. Intention is like the soul, and actions like the body : if the soul leaves the body, the body dies. Therefore, knowledge of the affairs of the heart is more important than knowledge of the affairs of the limbs ... How else is a hypocrite distinguished from a believer except by the deeds of the heart? The worship and submission of the heart is greater than the worship and submission of the limbs, they are more in number, and more continuous, since it (i.e. worship by the heart) is obligatory at every instance."
1 A Dictionary of Modern Written Arabic, p.320.
2 Ma/moo' al-Fatawâ, vol. 10. p.5.
3Badua'i' al-Fuwâ'id, vol.3, pp.224 & 330.