Ships are a Sign of the Mercy of Allah
Allah tells us of His kindness towards His servants by subjugating for them ships on the sea. He makes it easy for them to use ships to serve their interests, seeking His bounty through trade between one region and another. He says:
إِنَّهُ كَانَ بِكُمْ رَحِيمًا
(Truly, He is ever Most Merciful towards you.) meaning, He does this for you out of His grace and mercy towards you.