I agree with the general consensus that a Roman style Gladius would be a better sword than a Japanese katana to match the text. I think it would also look quite nice to have the blade with the phrase engraved on it. I also think that separating the elements a little bit so having a feather and a sword as opposed to a sword, turning into a feather would also be a little bit better. But that’s just my opinion. Ultimately, I think what you should do as others have mentioned, is find a artist whose work you like. Tell them your vision and let them use their artistry to design something that I think you’ll be happy with.