Basically you use the egg as a hint of what the person who wants the art could receive and then let the person also add in some of their own suggestions for detail.
Here is an example of a finished one. I'd show more, but this artist tends to do nsfw stuff and I haven't found another good artist who has done this project.
Romans 8:31 What, then, shall we say in response to this? If God is for us, who can be against us?
1 Corinthians 13:1-3 If I speak in the tongues of men or of angels, but do not have love, I am only a resounding gong or a clanging cymbal. If I have the gift of prophecy and can fathom all mysteries and all knowledge, and if I have a faith that can move mountains, but do not have love, I am nothing. If I give all I possess to the poor and give over my body to hardship that I may boast, but do not have love, I gain nothing.