In the first example, we get a comment of Abigail's character. We learn that Abigail is reaching out to Mary Warren "out of her infinite charity." This statement is clearly ironic, as we know that Abigail is not charitable. And even if she was, we know that Abigail does not care about Mary Warren.
This ironic statement develops the idea that people do not always mean what they say. Abigail acts in a way that seems kind and uninterested while she is actually plotting terrible schemes. This is similar to the role of Hale when he comes back to Salem.
Hale is a man who wants the procedures to be fair, yet he advises the accused to lie. This is a contradiction. Hale argues that the contradiction comes from the fact that he knows how corrupt the trials are, and that saving these people's lives is more important than being honest. He tells us that "life is God's most precious gift; no principle, however glorious, may justify the taking of it."
