Uphold me according to your promise, that I may live, and let me not be put to shame in my hope!
We cry to God because he hears us.
God does not save us because we call out to him. Instead, we call out to him because we his word promises to us he is faithful. God does not suddenly become faithful when we encounter trials and distresses. He does not suddenly turn a good ear to us when life is hard. God has been eternally faithful to himself and his people. He has always been, and always will be, faithful; therefore we can come to him for grace and mercy anytime.
Our cries do not cause God to come with a strong arm of salvation. His faithful, strong arm of salvation gives us a living hope, which is sure even in the darkest of times, so that we can be confident when we cry to him.