# Now what do I have here ... seeing that my people are taken away for nothing?

"Now look at what is happening ... my people are again taken away for nothing." 

# this is Yahweh's declaration

"this is what Yahweh has declared" or "this is what I, Yahweh, have declared"

# seeing that my people are taken away for nothing

"I see the enemy taking my people away for nothing"

# Those who rule over them mock

This refers to the Babylonians who have conquered the people. However, some versions have, "Those who rule over them wail." For these versions, this passage refers to the leaders of the Israelites in captivity.

# my name is blasphemed continually all day long

"those who watch the enemy take away my people are continually saying evil things about me"