It is very simple to push multiple messages onto the queue as a single JSON object.
- Create an array of messages
- Serialize it as JSON
- Push the serialized JSON onto the queue
This is how to encode the messages:

This is what the encoded JSON message looks like:

This is how to decode the messages:

Note: We encoded the messages into JSON in a From Translator. Then we used the encoded JSON message as sample data, in a To Translator, to test the decoding.
Here is the code that you can copy:
Encoding:
function main(Data)
local Messages = {}
Messages[1] = 'My first message'
Messages[2] = 'My second message'
queue.push{data=json.serialize{data=Messages}}
end
Decoding:
function main(Data)
local Messages = json.parse{data=Data}
for i = 1, #Messages do
-- do something with Messages[i]
trace(Messages[i])
end
end