Ecclesiastes said that "all is vanity," Most modern preachers say the same, or show it By their examples of true Christianity: In short, all know, or very short may know it.
If you really want the good of others, the whole universe may stand against you and cannot hurt you. It must crumble before your power of the Lord Himself in you if you are sincere and really unselfish.
Practice is absolutely necessary. You may sit down and listen to me by the hour every day, but if you do not practice, you will not get one step further. It all depends on practice.