Islam has three dimensions or levels, which in Arabic are called Islam, Iman, and Ihsan. Islam (submission) refers to having the correct actions, that is, ones that are in accordance with the Quran and Sunna. Iman (faith) refers to having the correct knowledge (Aqidah). Ihsan (excellence) refers to having the correct motivations.
Much attention is given to islam and iman and to matters of Shari’a and aqidah. But ihsan is important too. Having the correct motivations means purifying our souls from Arrogance, Envy, Hypocrisy, Caprice, Heedlessness, and everything else that keeps us from serving Allah for His sake alone. This purification of the soul is called Tazkiyah.