For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
Anyone can exemplify good morals e.g. follow 7 do all 10 commandments,plus...however, we must have an intimate relationship with Jesus Christ as Savior.
Ecc 7:20 For there is not a just man upon earth, that doeth good, and sinneth not.
Ps.14:1The fool hath said in his heart, There is no God. They are corrupt, they have done abominable works, there is none that doeth good.
Therefore, based on these two verses: a person cannot exemplify that which is not in him/her,because "no good thing dwells in the flesh".
Neither theists nor atheists can prove or disprove the existence or non existence of God. The only logical and moral state is to be agnostic and in particular a Christian agnostic who lives by these words of Jesus. "I am the way, the truth, and the life" and "love your neighbor as yourself." There is no better way to define a Christian or a way of living a moral life than by loving your neighbor!
The statement that "christians" act morally "out of the knowledge of the law given to them by the Lord in His word and a love for the law-giver Himself" sounds very spiritual, and speaks well of the people of God. But, I don't believe it can be applied to most of us. A great many "christians" learned obedience to a set of moral principles long before ever becoming a believer in the Lord. A good home life during childhood is responsible for good behavioral health more often than a life given to the Lord at a much later time of life.
Atheists, people who have YET to come to a saving knowledge of the Lord are many times raised with the same moral values as those who HAVE COME to a saving knowledge of the Lord.
Behavior is not a good indicator that a person has repented of sin and is trusting in the sacrificial life, death, and ressurection of the Christ, sent by the Father to redeem those who believe in Him.
The sooner the church and believers abandon this heretical doctrine the better the amazing grace of God will be understood and glorified.
We believers in the grace of God shown to us in the Christ have nothing to boast about except our boasting in the Christ. Except that we were chosen by God in Christ before the foundation of the world, we would have the same fate of the atheist, regardless of moral habits.
Being a Christian means accepting Jesus Christ as your savior. Being an Atheist means not accepting anyone or anything as their savior. Morality is taught and experienced. The Bible contains proper morality concepts. So did the Hammurabi writings. The Old Testament prophesied the coming of a Messiah and contains moral instructions for the Jews.
I have known many people from many countries and beliefs; Atheists, Buddhists, Taoists, Hindus, Jews, etc. They were all moral people in my estimation and were not believers in Jesus Christ. They all knew who Jesus was. The Bible (except for the OT believers) was not their source of morality, but they were moral people.
The question concerning Atheists and morality is quite simple to answer. Yes, there are Atheists who are moral people. In contrast, there are plenty of Christians who are not moral people. One cannot lump all Christians or Atheists in some kind of specific category. Generalizing usually gets one in trouble. You can only judge a person's morality from their behavior and words on a personal level.
Being respectful, kind, loving, etc., to one another comes from within. Whether that comes from a love of Jesus Christ, Allah, Buddha, Confucius, Joseph Smith, the Sun or anything or anyone else really doesn't matter. The source of one's morality is personal.
One's behavior is also personal. I try to base my morality on many things. My primary source is the Bible. Alternate sources are my upbringing, my environment and my interactions with people I've encountered in my life. I try to use my relationship with Jesus as an ultimate guide to morality. But it isn't my only source.
You don't have to be a believer in Jesus Christ to be a moral person. It does help, though.