1)
What is the meaning of "Lo Yasi Oyev Bo"?
1.
Rashi: The enemy will not overpower him, to be like a creditor to him.
2.
Radak: The enemy will not be like his creditor, to take his money.
3.
Malbim: An Oyev himself does not afflict or make others hate him - those are attributed to Tzar and Masni (refer to 89:24:2:1). Rather, he reveals his hatred verbally, and makes false accusations.
2)
What is "Ben Avlah"?
1.
Radak: Also this is an enemy.
2.
Malbim: It is one who afflicts in practice; the verse promises that he will not be able to do so.