I don't know what Francis means by "you must take things as they come."  As often happens, his lack of clarity invites misunderstanding.  But reading his comments as a whole, it seems he is simply trying to emulate Christ's approach to the woman at the well.  Christ did not immediately condemn her, but out of love, corrected her and tried to set her on a new, Godly path.  If Francis is instructing us to approach sinners this way --- aren't we all? --- who could argue?  If on the other hand, he is advocating situation ethics, there would obviously be a lot more to say.