The Quran

يا أَيُّهَا الَّذينَ آمَنوا إِنَّمَا المُشرِكونَ نَجَسٌ فَلا يَقرَبُوا المَسجِدَ الحَرامَ بَعدَ عامِهِم هٰذا ۚ وَإِن خِفتُم عَيلَةً فَسَوفَ يُغنيكُمُ اللَّهُ مِن فَضلِهِ إِن شاءَ ۚ إِنَّ اللَّهَ عَليمٌ حَكيمٌ

Muhammad Asad

O YOU who have attained to faith! Those who ascribe divinity to aught beside God are nothing but impure:¹ and so they shall not approach the Inviolable House of Worship from this year onwards² And should you fear poverty, then [know that] in time God will enrich you out of His bounty, if He so wills:³ for, verily, God is all-knowing, wise!

The term najas ("impure") occurs in the Qur'an only in this one instance, and carries an exclusively spiritual meaning (see Manar X, 322 ff.). To this day, the bedouin of Central and Eastern Arabia - who, contrary to the modern town-dwellers, have preserved the purity of the Arabic idiom to a high degree - describe a person who is immoral, faithless or wicked as najas. "The Inviolable House of Worship" (al-masjid al-haram) is, of course, the Ka'bah and, by implication, the whole of the territory of Mecca: which explains the next sentence.
Lit., "after this their year" - i.e., after the year 9 H., in which this surah was revealed.
This is an allusion to the apprehension on the part of some Muslims (and not only at the time of the revelation of this verse) that an exclusion of unbelievers from living in or visiting Mecca might lead to a loss of its position as a centre of trade and commerce, and thus to an impoverishment of its inhabitants.