Faithfulness to God leaks into relationships with people. The way we love God has to spill into the way we treat the people that He has made. The Golden Rule of Jesus isn't hard to understand, but it does prove quite difficult to apply.
"And what does your anxiety do? It does not empty tomorrow of its sorrows; but, oh, it empties today of its strength. It does not make you escape the evil, it makes you unfit to cope with it when it comes. It does not bless tomorrow, and it robs today. For every day has its own burden. Sufficient for each day is the evil which properly belongs to it. Do not add tomorrow's to today's. Do not drag the future into the present. The present has enough to do with its own proper concerns." - Alexander Maclaren