# the Sabeans

This refers to a group of raiders or bandits in a region of modern day Yemen.

# fell on them

"attacked them"

# have struck

Here striking represents killing.

# the edge of the sword

Here "edge" represents the part of swords that kill people, that is, either the point or the sharp edge. Also, all the swords of the Sabeans are spoken of as if they were only one sword.

# I alone have escaped to make it known to you

"I am the only one who has escaped and can report it to you"

# make it known to

"tell"