To me, its a difference like day and night. Adopting a theistic world view, i can know God, and experience his grace and love of a loving father. Its a joy to be able to witness to others about the greatness of God. In that way, i am making a difference in this world, and my life has also value for others. It means loving and being loved by others. Furthermore, i find meaning , self worth, and ultimately it makes a difference, how i live, and who i am, and what i do today, has significance and consequences also in eternity. My life is not doomed when i die, rather i have the perspective of living eternally with God. So belief in God gives me hope for a eternal life in heaven. Furthermore, i find peace with God through the forgiveness of my sins, through Christ's death on the cross. Without faith in God, there is no hope of deliverance of unjustice and evil. Nor are there objective moral values. Everything becomes subjective and relative, and depends entirely on each individuals standpoints. Ultimately, there is no good, and no evil. There are just different viewpoints and standards based on personal preferences. Furthermore, the existence of the universe and life makes sense and its existence is explained in a satisfiying manner through a creator. In a broader sense, Christianity has shaped western civilisation in many ways for the better. The Bible itself is responsible for much of the language, literature, music and fine arts we enjoy today as its artists and composers were heavily influenced by its writings. The liberties and human rights of secular governments , freedom and rights of the individual, and so the criminal and justice system are direct consequence of the bible, and so the belief that man is accountable to God and that the law is the same regardless of social position, power and wealth. The education system, care of orphans and the elders, and hospitals goes back to the spread of monasteries, which were taking care of the general population. Science began to flourish in the western world, like Occam's razor in the twelfth century , and many science fathers, like Galilei, Newton, Volta, Ohm, Ampere, Kelvin, Faraday etc. were all Christians. There are many other things, but this is just to name a few.
If you're talking about many of the first orphanages, all of our major Ivy League universities in fact all but one the first 123 colleges and universities in colonial America, almost every charitable organization i.e. the Red Cross, Nursing (Florence Nightingale), the abolition of slavery in both the Roman world and the European Slave Trade, ALL of the first sciences including the scientific method (as we know it today), Kepler, Newton, Pasteur, Boyle, Maxwell, Steno, Martel, ect; free enterprise and work ethic (ethics in general), wherever there are starving people, there are Christians feeding, wherever there are homeless, Christians are building shelters, in Rome during a plague Christians would not flee but tend for the sick and dying, the greatest contributions to music, literature, and art who brought them to music theory and even revolutionizing literature as we know it today are all contributed to Christians and Christianity.
"This is our culture's powerful emphasis on compassion, on helping the needy, and on alleviating distress even in distant places. If there is a huge famine or reports of genocide in Africa, most people in other cultures are unconcerned. As the Chinese proverb has it, 'the tears of strangers are only water.' But here in the West we rush to help....Part of the reason why we do this is because of our Christian assumptions....The ancient Greeks and Romans did not believe this. They held a view quite commonly held in other cultures today: yes, that is a problem, but it is not our problem....However paradoxical it seems, people who believed most strongly in the next world did the most to improve the situation of people living in this one." -D'Souza