"You, my brothers, were called to be free. But do not use your freedom to indulge the flesh; rather, serve one another in love."
Those who have been set free by grace should not return to the old ways of doing things (that is, the Law). Giving to the poor does not make you good. Reading your bible does not sanctify. Fasting does not make you holy. Only God in heaven is capable of doing that. How foolish it is to try and earn by human effort what can only come through the Spirit! After receiving grace, will you now try to earn it? We were not saved due to our good works, but from believing the gospel which we had heard.
Those who are under grace are free to sin without eternal consequence. However, Paul states that in our freedom we choose no longer to sin but rather serve in love. When we sin, it is not because we wanted to sin, but Sin living in us (our fallen nature). It is no longer we who sin, but Sin living in us, but now it no longer causes our condemnation! Hallelujah!
Christianity is not based on Law, but on Grace. There is now forgiveness for sin in Christ Jesus. So don't you dare feel guilty you hadn't prayed more or fasted longer. Those things only serve to worship the One who makes us holy, not to make us holy. You were called to be free from such nonsensical thinking.