In the Name of Allah, the Compassionate, the Merciful.
In Ayah 5 of Surah Baqara we read:
أُولَـٰئِكَ عَلَىٰ هُدًى مِّن رَّبِّهِمْ ۖ وَأُولَـٰئِكَ هُمُ الْمُفْلِحُونَ
"Those follow their Lord's guidance, and it is they who are the felicitous." (2:5)
This Ayah means to say that fate of the sincere and clean-hearted people is happiness and felicities.
It elucidates that this happiness is attainable through accepting of divine guidance. Felicities mean getting rid of carnal and base desires. It means developing of moral traits. In the Arabic language the 'farmer' is Fallah, because his action of sowing enables the seeds to cut open the soil and sprout in the form of plants.
Thus the word "Muflehun" as used in the original Arabic of this particular ayah is a derivative of the same root and means those who are the successful. That is to say, a person who follows God's commands comes out triumphant and relieved. Relief is the highest point of human perfection, since according to the Qur'anic Ayahs the whole uniAyah is created for the sake of mankind and the duty of mankind is to obey and worship the Almighty Creator, in order to attain piety and become successful and prosperous in the real sense of the term.
From this Ayah we learn that:
1. The way to attain relief and eternal bliss is to accept divine guidance.
2. Relief is not attained without effort. It needs knowledge, faith, and good deeds.
Now here is the 6th Ayah of the same Surah:
إِنَّ الَّذِينَ كَفَرُوا سَوَاءٌ عَلَيْهِمْ أَأَنذَرْتَهُمْ أَمْ لَمْ تُنذِرْهُمْ لَا يُؤْمِنُونَ
"As for the disbelievers, it is the same to them whether you warn them or not warn them, they will not have faith." (2:6)
Having dwelt on the characteristics of the believers this Ayah talks about the disbelievers, and means to say they are persons who are obstinate and blind to the manifest truth, to the extent that they vehemently oppose the right path. The words of Prophets and their mission do not have any effect on such petrified hearts. The word "Kufr" in Arabic literally means concealing and ignoring.
Thus, "Kafir" is a person who tries to conceal realities, opposes righteousness and ignores it. If God had willed all people would believe by force, yet belief and faith ought to be of free will and not through compulsion, because in such a case faith will have no meaning. God decreed man to embrace the right path whole-heartedly and with proper cognizance. Thus we should not expect all human beings to be true believers since there are many who see the truth but deny it for a variety of selfish reasons.
From this ayah we learn that:
1. Kufr, or prejudice and obstinacy rob persons of their humanitarian feelings and turn them into insensitive objects such as wood or stone. Thus such persons become oblivious and practically deaf and blind to wise words and advices.
2. The mission of the Prophets is like rain which can only be effective and fruitful when it falls on a fertile soil and not on salty or infertile land.
3. We shouldn't give up our duty of promoting God's words and warning the unbelievers even if we know that they will not accept the truth.
Now let's listen to Ayah 7 of Surah Baqara:
خَتَمَ اللَّـهُ عَلَىٰ قُلُوبِهِمْ وَعَلَىٰ سَمْعِهِمْ ۖ وَعَلَىٰ أَبْصَارِهِمْ غِشَاوَةٌ ۖ وَلَهُمْ عَذَابٌ عَظِيمٌ
"Allah has set a seal on their hearts and their hearing, and there is a blindfold on their sight, and there is a great punishment for them." (2:7)
The unbelievers have also been given eyes, ears and all other human faculties including the intellect and the power of speech, but because of their indulgence in evil, they lose the ability to understand, see and listen to the facts. This is a sort of punishment for them from God in this world and the more excruciating chastisement awaits them in the Hereafter.
Now there might pass a question in one's mind that: If God has set a seal on the hearts, eyes and ears of the unbelievers they have no choice or authority, therefore, their being unbelievers is justifiable.
The answer to this question is clearly stipulated in part of Ayah 35 of Surah Ghafer or Mo'men where Allah says:
"…That is how Allah seals the heart of every arrogant tyrant."
Also in part of Ayah 155 of chapter an-Nisa we read:
"…Rather Allah has set a seal on them for their disbelief."
Indeed these Ayahs explain the divine unchangeable law, that is, if a person indulges in arrogance, superciliousness and stubbornness vis-a-vis God's wise commandments and signs, he or she will lose the means of realizing and distinction between right and wrong, to the extent that he or she will become miserable in this world and in the afterlife.
The lessons we learn form this ayah are:
1. A person who has understood the right but still denounces it God will set a cover on his faculties of understanding - eye, ear and heart. This is God's punishment.
2. It is wisdom, understanding and insight that make man superior to other creatures but he will lose this privilege by indulging in Kufr.