(I am only a human being like you. It is revealed to me that your God is One God,) `not like these idols and false gods which you worship. Allah is one God,'
فَاسْتَقِيمُواْ إِلَيْهِ
(therefore take straight path to Him) means, `worship Him Alone sincerely, in accordance with what He has commanded you through His Messengers.'
وَاسْتَغْفِرُوهُ
(and seek forgiveness of Him) means, `for your past sins.'
وَوَيْلٌ لِّلْمُشْرِكِينَ
(And woe to the polytheists.) means, doom and destruction is their lot.
لَهُمْ أَجْرٌ غَيْرُ مَمْنُونٍ (For them there is a reward that will never be interrupted 41:8) The word mamnun used here means something interrupted. The sense is that the reward of those people who are firm in their faith and regular in their good deeds would be continuous and eternal. Some exegetes have explained the intention of the verse that if a Muslim, despite being regular in religious duties, could not perform them at any time due to illness, travel or some other reason, the reward for the good deeds is not cut off. Rather, Allah Almighty orders the angels to keep on crediting those good deeds to his account which he used to carry out regularly in normal conditions, but could not do them due to illness or some other reason. Ahadith on this subject are narrated in Sahih of Bukhari as reported by Sayyidna Abu Musa Ash'ari and in Sharh-us-Sunnah of Baghawi by Sayyidna Ibn ` Umar and by Sayyidna Anas ؓ and in Razin by Sayyidna ` Abdullah Ibn Masud ؓ . (Mazhari)
Tazkirul Quran
Maulana Wahiduddin KhanOn ayahs 8–11
Whenever the call for Truth is issued, it takes place at the level of human beings. But people are unable to understand how it is possible for a man to speak in the language of God, and therefore they deny his message. But God communicates his message through a human being. One who cannot see beyond the humanness of the prophet and recognise the divineness of the message delivered by him, must remain deprived of God’s guidance in the present world of trial. Only that belief in the Hereafter is reliable which is accompanied by a firm belief in the oneness of God and the giving of alms for the sake of God’s pleasure. One who truly finds God can never be held in thrall by the greatness of any other being. Similarly, one who truly finds God cannot prevent himself from spending his wealth for the cause of God. ‘So take the straight path to Him’ means ‘keep your worship purely for God’, i.e. your whole attention should be directed towards God; the sole object of your prayers and worship should be the one and only God; your entire thinking should become God-oriented. God’s perpetual blessings will be showered on those who conduct themselves in this way.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.