The Four Levels of Remembrance
Imām Ibn Taimiyyah, may Allāh have mercy on him, said:
People, with regard to remembrance of Allāh, are upon four levels. [The first] is remembrance with the heart and the tongue: that is what has been commanded [of us].
[The second] is remembrance with the heart alone: if it’s [because] the tongue is unable [to speak], then it’s fine, [but] if it’s with [the tongue] being capable, then it’s [a person’s] leaving off doing something that is better.
[The third] is remembrance with the tongue alone: that is [a person’s] tongue remaining fresh with the remembrance of Allāh […].
[The fourth] is absence of the two, [no remembrance of the heart, nor of the tongue]: that is state of those who face [tremendous] loss.
Majmūʿ Al-Fatāwá, vol. 10, p. 566.