In the OT, the feast of Weeks (Exod. 34: 22), an agricultural festival on which work was forbidden (Lev. 23: 21). Later, the festival was incorporated into Israel's national consciousness of its history and became associated first with the covenant made with Noah (Gen. 8: 20–22) and then with the giving of the Law on Mount Sinai. Because the interval between the first Passover and the arrival at Sinai was reckoned as fifty days (Exod. 19: 1), the feast became established after that interval, as is seen from the NT (Acts 2: 1–42), where the Greek word ‘Pentecost’ is current. The narrative in Acts 2 resounds with echoes of the giving of the Law at Sinai. First there is the contrast, for Christians, as Paul taught, now live under the Spirit rather than the Law. Secondly, there is the resemblance: the visible gift of the Spirit was in the form of tongues of fire, and the author of Acts is recalling the descent of the Lord in fire on Sinai (Exod. 19: 18). Thirdly, the ‘harvest’ of 3,000 converts recalled the harvest of the old OT agricultural context of the feast (Exod. 23: 16). The gift of languages, as the glossolalia is interpreted, marks the reversal of the scattering of nations at Babel (Gen. 11: 1–9). Therefore Pentecost continued to have special significance in the Church (1 Cor. 16: 8; Acts 20: 16) as the festival of unity (1 Cor. 12: 13), a foretaste and promise of a unity among all the nations of the world through the gospel (Acts 1: 8; 10: 45).