How to print multiple arrays into one single message box?

Hi, how can I print a number of arrays (not fixed) into a message box?

For example:
arrayX = {“1”, “2”,…}
arrayY = {“A”,“B”,…}

I only want one single message box to show all data together:
“1 A
2 B”

The number of arrays is not fixed and is random depending

I have just free time:

outTxt=arrayX(k-1)+" "+arrayY(k-1)+chr(10)+outTxt