Does it matter what MAN thinks or believes? God does not need anything from man (Acts 17:24-25). However......the most ardent supposed atheist will call out for help from the "invisible" God in his/her lifetime under the correct circumstances (I have seen this over my military career)........an atheist is someone that is yet to encounter said circumstance, and remains "puffed up" with pride in worshisping self, as if the created is greater than the creator. There is hope even for a reprobate mind as long as life exists.
"Not for your sacrifices do I rebuke you; your burnt offerings are always before Me. I will not accept a bull from your house or goats from your folds. For every beast of the forest is Mine, the cattle on a thousand hills, and all that moves in the field is mine. If I were hungry, I would not tell you, for the world and its fullness are Mine. Do I eat the flesh of bulls or drink the blood of goats? Offer to God a sacrifice of thanksgiving and perform your vows to the Most High, and call upon me in your time of trouble, and I will deliver you, and you shall glorify Me." -- Ps. 50:8-15
In other words........God does not look upon physical things and possessions the way man does, God needs nor requires nothing from man, the rituals and sacrifices are more for man than God, God wants Spiritual sacrifices that come from the heart rather than things that men consider important, God would have men serve Me with "gratitude" and "thanks" in their heart ..........and He will answer you in your time of need, God needs nothing from man.
Its clear........God is a Spirit that requires nothing physical unlike man......as Jesus stated, most go through life "worshiping" what they know not. We must serve God in Truth and Spirit (John 4:21-24). Anything less is worthless to both man and God. God does not need the atheist to exist, for the atheist cannot see what he cannot comprehend........the Spiritual side of reality. We must make Spiritual Sacrifices in honor of the Creator that caused this reality called life.
The Apostle stated it best in clear unambigous fashion, "For I am seeking the approval of man, or of God? Or am I trying to please man? If I were still trying to please man, I would not be a servant of Christ." -- Gal. 1:10
The Apostle understood, once a reprobate toward Jesus (God incarnate).......he fell into the hands of the living God, once there, there is no return........for your eternal soul is required and that is a fearful thing, "It is a fearful thing to fall into the hands of the Living God." -- Heb. 10:31
The atheist can think and reason as he/she will.........I have no control in realtion to the thoughts of others, but........"As for me and my house.......we shall serve the Lord." -- Joshua 24:15