Question: If those who do not have any good deeds or acts of worship and who spend their years sinning say the Kalima-i shahadat with ikhlas and die with this faith, will they go to Jannat [Paradise]?
ANSWER
It is very difficult for those who shun acts of worship and who are totally immersed in sins to die with iman. However, if they should die with iman, they will certainly go to Paradise after being subjected to punishment as much as their sins.

We should not underestimate the importance of good deeds and acts of worship. A good deed that we consider trivial may cause us to attain salvation. A hadith-i sharif says:

(A Muslim who had not done any good deeds in his life removed a thorn from a road [lest it would prick another Muslim’s foot]. This deed of his was accepted before Allah, and he entered Paradise.) [Abu Dawud]

Question: It is said that those with a mote of iman will certainly go to Paradise. What is meant by “a mote iman”?
ANSWER
A person who has belief in the six facts expressed in the Amantu (the prayer that states the six fundamentals of faith) and who also says “I believe, like, and accept all of what Hadrat Muhammad communicated” has obtained this a mote of iman.

If one says, “Allah’s Mercy is immense, so it is not necessary to say ‘Muhammadun Rasulullah,’” in this case, the connection with Islam is severed, so there is not a mote of iman. A hadith-i sharif says:

(He who has obtained a mote of iman by saying “La ilaha ill-Allah Muhammadun Rasul-Allah” will be taken out of the Fire.) [Bukhari, Muslim, Tirmidhi]
If one believes in the six fundamentals of belief but if one does not believe in one thing among them, e.g.,any of the prophets, or if one does not like one of the fards or sunnats, then one cannot be a Muslim. In other words, one is not considered to have faith in the six fundamentals of belief.

On the other hand, in order to die with a mote of iman, people must avoid what is prohibited and perform  acts of worship because the sins they commit may extinguish the light of iman. That is, those sins may lead them to disbelief.

Question: Will all people who say the Kalima-i shahadat and have died with iman definitely go to Paradise?
ANSWER
Those with a mote of iman will definitely go to Paradise. Even so, a person who does not perform acts of worship and who does not abstain from sins cannot safeguard their iman and falls into disbelief (apostasy). However, the abode of a person who safeguards it will certainly be Paradise.

Hadrat Mu’adh narrates:
The Messenger of Allah stated, “O Mu’adh! What is the right of Allahu ta’ala on His born servants and His born servants on Him?” I replied, “Allah and His Messenger know better.” Upon this, he declared, “Allahu ta’ala’s right on His born servants is that they should worship Him [by believing as He commanded and by liking] and should not attribute partners to Him. His born servants’ right on Allah is that He will not punish anyone who does not attribute a partner to Him.” When I asked, “O Messenger of Allah! Shall I give this good news to people?” he answered, “No, you shall not. Then they depend on it, and as a result, they may give up doing good deeds [they may ignore the other acts of worship, and thus, they may be drifted into perdition].” (Bukhari, Muslim, Tirmidhi)

When Allah’s Messenger said, “Allahu ta’ala has made the Fire haram for all people who testify with sincerity that there is no god except Allah and that Muhammad is Allah’s Messenger [and who safeguard this faith and die Muslims],” I asked him, “O Messenger of Allah! Shall I inform people of this fact?” He declared, “Then they depend on it and give up good deeds.” (Bukhari, Muslim, Tirmidhi)

Hadrat Mu’adh, in order to extricate himself from the sin of withholding what one knows from others, informed people of this fact a little before his death.

Question: Will Muslims who commit grave sins go to Paradise, too?
ANSWER
If they get benefit from shafa’at [intercession], they will go to Paradise without entering Hell at all. Shafa’at will be for grave sins. Those with a mote of iman will be blessed with a great blessing on the Day of Resurrection. Our master the Prophet swears that these are facts:

(I am telling the following by swearing:
1. Even a Mu’min who is fajir [who commits various sins] and who is so idiot as not to earn his livelihood will go to Paradise.

2. He who is burned in Hell-fire on account of his sins will go to Paradise.

3. On the Rising Day, Allahu ta’ala will forgive Mu’mins in a manner undreamed of by anyone.

4. Allahu ta’ala will forgive so many people that even Iblis will raise his head, thinking whether he, too, may be forgiven.) [Bayhaqi]

(Whoever has the following qualities, Allahu ta’ala makes Hell haram for his body and protects him against Shaitan and his nafs: He who curbs his nafs and does not go after it when it craves for something [which is sinful] and who does it [a good deed or an act of worship] when his nafs does not want it overwhelms the desires and fury of his nafs. Also, whoever has the following qualities, Allahu ta’ala, inundating him with His Mercy, puts him into His Jannah: providing shelter for a poor person; feeling sorry for a wretched one; treating your servant well; spending on your parents.) [Daylami]