There a many arguments put forward that fasting of the more ancient form is too difficult in the modern world – though I cannot understand the reasoning. We have too much food therefore we cannot refrain from certain foods? We’re too busy to pray? etc.
A thousand years ago there would have been no Christian in the world who did not fast or think of fasting as an integral part of his/her life. It’s growing disappearance is part of a vast sea-change that effected some of the most fundamental understandings of the faith.
It would sound odd to many were I to say, “There is no Christianity without fasting.” But this would not have sounded odd a thousand years ago.
Fasting is not a law. We can certainly be saved without it. We do not earn anything by fasting. But breathing is not a law. I do not recommend a Christian abstain from breathing. Fasting is simply a normative part of the Christian spiritual life – like prayer. It may even be the case that we can be saved without prayer – it’s just that I can’t imagine what that would look like.