What is the difference between a kafir and a fassiq?

[tariqa]

if one believes in his heart that Allah is the lord, but he doesnt act upon this, does this make him a kafir?



if one believes in his heart that Allah is lord, but he lies to people and denies this to fit in and be accepted, does this still make him a kafir?



does knowing something but not acting upon it makes one a kafir?


if thats the case then how come there are so man muslims that do not pray
arent they kafirs for their failure to act upon what they know and believe?

[BrotherOfIlm]

if one believes in his heart that Allah is the lord, but he doesnt act upon this, does this make him a kafir?

If one is accountable (sane, pubescent and heard the call of Islam) and does not act upon it, then he is a kafir/disbeliever/blasphemer. This is a standard rule in Islam.

if one believes in his heart that Allah is lord, but he lies to people and denies this to fit in and be accepted, does this still make him a kafir?

If one is a muslim at heart, and goes around saying he is not a muslim, i.e. a kaafir, is this not a saying as mentioned by the great scholars that turns you out of Islam? If one is to say such an abhorrent thing, for fear he is in immenent danger of losing his life, I think this is the only time one may do so, not to feel less "embarrassed" or to fit in, that is insulting to the deen of Islam.

does knowing something but not acting upon it makes one a kafir?

Such as what? Is this not the same as the 1st question? Please elaborate.

if thats the case then how come there are so man muslims that do not pray
arent they kafirs for their failure to act upon what they know and believe?

Acording to some scholars, ones who leave the prayer out are disbelievers due to their laziness of acting upon their belief, whereas others said it is not blasphemy, but a great/major sin.