Many Christians know better than to be superficial but sometimes the line blurs between maintaining ones personal image and obsessing over ones physical appearance.
As Christians, we serve as representatives of Christ to the world and are no less than the face of Christ. We have a responsibility to ensure our appearances do not lead others to misinterpret the values of Christianity. Although there is only a certain degree to which we can influence others without controlling their thoughts, our responsibility is to be conscious of a third-persons perspective.
One common practice among women is the use of make-up. Although using comsemetics to enhance ones own presentability, women should use apply the Biblical teaching of moderation to this practice. There may be a chance of women becoming too engrossed in the practice and will lose focus on what is most important the Kingdom of God. No Christian women would admit that their regard for physical appearance is comparable to the ultimate dream of God but the priorities of faith may be shifted if the women are not attentive to how much time they devote to maintaing their desired image.
A similar pitfall can be applied for Christian men who expend a great deal of their resources in body workout. The motive of keeping good health and developing a healthy physique can easily become an addiction where men religiously spend time and money going to gyms, buying protein shakes, and then eventually sporting tight muscle shirts.
Where an excessive amount of energy can be invested in physical appearance, the opposite can be just as devastating the message Christians send through their appearance. Too little regard for outer appearance can lead a third party to perceive Christians as being lazy or sloppy. There a standard of modesty Christians are called on to maintain but that standard does not call on Christians to be ascetic. Those who have found peace and love in Christ are like ones invited to a wedding banquet feast. Our attire should reflect our joy and convey a sense of nobility from being a child of God.
Although Christians are commissioned to be the salt and light of the world, preserving the good and bringing change to the bad, Christians must also have an awareness for cultural practices and how they can be interpreted. We should maintain our appearances well but just be wary of idolizing ourselves over something that warrants a greater attention - God and His Will.