Deuteronomy 33:18

Rejoice, Zebulun, in thy going out - That is, Thou shalt be very prosperous in thy coasting voyages; for this tribe's situation was favorable for traffic, having many sea-ports. See Genesis 49:13 ; (note).

And, Issachar, in thy tents - That is, as Zebulun should be prosperous in his shipping and traffic, so should Issachar be in his tents - his agriculture and pasturage.