Tafsir of Ya seen 36:44

إﻻ رحمة منا

Unless it be a mercy from Us, means, `but by Our mercy We make it easy for you to travel on land and sea, and We keep you safe until an appointed time.' Allah says:

ومتاعا إلى حين

and as an enjoyment for a while. meaning, until a time that is known to Allah, may He be glorified and exalted