A basic idea in Christianity is that you can do x, and if you align yourself to God, God through you can do x^n, say.*
What God does is good for you and good for society, so the idea goes. So why would you choose the former x?
The main answers are a) disbelief, or b) fear.
Both are met in the same way. Learn about and start to try out the practice of discernment. Start small if you want, and then see what results you get, but do it with an open heart – allow yourself that space to experiment for a bit. ‘Belief’ in God primarily just means trusting in God, and that means a relationship, and that means discernment, and then action.
Once you start to get results (it might be useful to record the results somewhere), reappraise. Iterate.
Anyone can try this – atheist or theist.
*(For example, let x = 10. Let n = 3. So, x = 10, x^n = 1,000. This mathematical relationship gets at the basic idea, where n in Christianity seems to be dependent on our openness to God and your practice of discernment, in particular. So the idea goes.)