The greatest love that Christians or the saved can give unto the unsaved is Jesus Christ. Share the gospel to the unsaved. Because how can they become saved unless they hear the gospel. How will the unsaved hear the gospel unless someone tells them. This is how I became saved and the vast majority of all the people who were saved, Someone told them about Jesus and they accepted and now they are saved and will live forever. So to me the greatest love Christians or the saved can give unto the unsaved is to share the gospel of Jesus Christ with them. For as worldly education or money or any material things are not going to do anyone any good for as eternal life if they do not have a relationship with their Creator.