'Merciless' in the Bible

‘All your lovers (allies) have forgotten you;They do not seek and long for you.For I have injured you with the wound of an enemy,With the punishment of a cruel and merciless foe,Because your guilt is greatAnd your sins are glaring and innumerable.

without understanding, untrustworthy, unloving, unmerciful [without pity].

For judgment will be merciless to one who has shown no mercy; but [to the one who has shown mercy] mercy triumphs [victoriously] over judgment.