(3:4) Before, as guidance for the people. And He revealed the Qur’an. Indeed, those who disbelieve in the verses of Allah will have a severe punishment, and Allah is exalted in Might, the Owner of Retribution.
Muhammad Taqi-ud-Din al-Hilali and Muhammad Muhsin Khan,
(3:4) Aforetime, as a guidance to mankind, And He sent down the criterion [of judgement between right and wrong (this Quran)]. Truly, those who disbelieve in the Ayat (proofs, evidences, verses, lessons, signs, revelations, etc.) of Allah, for them there is a severe torment; and Allah is All-Mighty, All-Able of Retribution.
Mohammed Marmaduke William Pickthall
(3:4) Aforetime, for a guidance to mankind; and hath revealed the Criterion (of right and wrong). Lo! those who disbelieve the revelations of Allah, theirs will be a heavy doom. Allah is Mighty, Able to Requite (the wrong).
Abdullah Yusuf Ali
(3:4) Then those who reject Faith in the Signs of Allah will suffer the severest penalty, and Allah is Exalted in Might, Lord of Retribution.
Mohammad Habib Shakir
(3:4) Surely they who disbelieve in the communications of Allah they shall have a severe chastisement; and Allah is Mighty, the Lord of retribution.
(3:4) Earlier, as guidance to mankind, and He sent down the all-distinctive Criterion. Surely (the ones) who have disbelieved in the signs of Allah will have a strict torment, and Allah is Ever-Mighty, Owner of vengeance.
(3:4) In time past, as guidance for the people; and He has sent down the Criterion to distinguish between truth and falsehood, and the knowledge, and power of judgment to put it into effect. Those who disbelieve in the Revelations of God, for them is a severe punishment. God is All-Glorious with irresistible might, Ever-Able to Requite.
Amatul Rahman Omar
(3:4) Before this, as a guidance of the people. And He has revealed (the Qur´ân as) the Criterion of judgment (between truth and falsehood). Those who deny the revelations of Allâh there surely awaits them a severe punishment. Mighty is Allâh, the Lord of Retribution.
(3:4) From before guidance to the people, and He descended the Separator of Right and Wrong/Koran , that those who disbelieved with God`s verses , for them (is) a strong (severe) torture, and God (is) glorious/mighty , (owner) of a revenge/punishment.
(3:4) Before this as guidance for men, and has sent the criterion (of falsehood and truth). As for those who deny the signs of God, the punishment is severe; for God is all powerful and great His requital.
A. J. Arberry
(3:4) aforetime, as guidance to the people, and He sent down the Salvation. As for those who disbelieve in God’s signs, for them awaits a terrible chastisement; God is All-mighty, Vengeful.
Abdul Majid Daryabadi
(3:4) Aforetime, for a guidance unto the people, and sent down the criterion. Verily those who disbelieve in the signs of Allah Unto them shall be torment severe. And Allah is Mighty, Lord of Retribution.
Maulana Mohammad Ali
(3:4) before as a guide for the people and now He has revealed the criteria of discerning right from wrong. Those who reject the revelations of God will face the most severe torment. God is Majestic and capable to revenge.
Hamid Abdul Aziz
(3:4) Verily, those who disbelieve in the signs of Allah, for them is a severe penalty, for Allah is Mighty and Avenging.
(3:4) Before this, a guidance to mankind
(3:4) Aforetime, as guidance for mankind; and He sent down the Criterion. Those who have rejected Gods signs will have a severe punishment. God is Mighty, Able to take revenge.
Ahmed Raza Khan
(3:4) Before this, a guidance to mankind; and sent down the Judgement (Criterion to judge between right and wrong); indeed for those who disbelieved in the verses of Allah, is a severe punishment; and Allah is the Almighty, the Avenger (of the wrong).
(3:4) in the past as guidance for mankind; He has [also] sent down the Standard by which to discern the true from the false. Surely those who deny God’s signs will suffer severe punishment. God is mighty and capable of retribution.
(3:4) Aforetime, as a guidance to mankind. And He sent down the criterion. Truly, those who disbelieve in the Ayat of Allah, for them there is a severe torment; and Allah is All-Mighty, All-Able of Retribution.
Ali Quli Qarai
(3:4) before as guidance for mankind, and He has sent down the Criterion. Indeed, there is a severe punishment for those who deny the signs of Allah, and Allah is all-mighty, avenger.
Hasan al-Fatih Qaribullah and Ahmad Darwish
(3:4) before, as a guidance for people, and He sent down the Criterion. As for those who disbelieve in the verses of Allah, for them is an intense punishment. Allah is Mighty, Owner of Vengeance.
That is translated surah Ali ‘Imran ayat 4 (QS 3: 4) in arabic and english text, may be useful.