Back 
Surah 30. Ar-Rum
Ayah 46 - 47
46 وَمِنْ ءَايَـٰتِهِۦٓ أَن يُرْسِلَ ٱلرِّيَاحَ مُبَشِّرَٰتٍ وَلِيُذِيقَكُم مِّن رَّحْمَتِهِۦ وَلِتَجْرِىَ ٱلْفُلْكُ بِأَمْرِهِۦ وَلِتَبْتَغُوا۟ مِن فَضْلِهِۦ وَلَعَلَّكُمْ تَشْكُرُونَ
47 وَلَقَدْ أَرْسَلْنَا مِن قَبْلِكَ رُسُلًا إِلَىٰ قَوْمِهِمْ فَجَآءُوهُم بِٱلْبَيِّنَـٰتِ فَٱنتَقَمْنَا مِنَ ٱلَّذِينَ أَجْرَمُوا۟ ۖ وَكَانَ حَقًّا عَلَيْنَا نَصْرُ ٱلْمُؤْمِنِينَ
[46-47] Of His Signs is this that He sends the winds to give good news68 and to bless you with His Mercy and to make the ships sail by His Command,69 so that you may seek His bounty70 and be grateful to Him. And We sent before you Messengers to their peoples who came to them with clear Signs.71 Then We took vengeance on the guilty ones72 and it was their right on Us that We should help the believers.
68That is, to give good news of the rain.
69This refers to winds, which are helpful in sailing. In ancient times, sailing boats and ships mostly depended on favorable winds and adverse winds were disastrous for them. Therefore, the mention of these winds after the rain bringing winds has been made as a special favor of Allah.
70"To seek His bounty": To perform trade journeys.
71That is, "One kind of the Signs are those which are scattered in the world around man, which he comes across at every moment of his life, one of which is the system of the circulation of winds, as mentioned in the preceding verse. The other kind of the Signs are those which the Prophets of Allah brought in the form of the miracles and Divine Revelations and the extraordinary pure characters and their healthy and life-giving influence on human society. Both kinds of the Signs point to the same Reality, which is this: The Tauhid which the prophets teach is based on the Truth. Each of these Signs supports the other. The Signs of the universe testify to the truth of what the Prophets say, and the Signs brought by the Prophets explain the reality being pointed out by the Signs of the universe.
72"The guilty ones": those who remained blind to these two kinds of the Sighs and persisted in their denial of Tauhid and their rebellion against God.