"Then the eyes of both of them were opened, and they knew that they were naked; and they sewed fig leaves together and made themselves coverings" (Genesis 3:7, NKJV).
Before Adam and Eve sinned against God, Scripture says "they were both naked, the man and his wife, and were not ashamed" (Genesis 2:25). However, with sin's entrance into the world, they perceived their nakedness, prompting them to make loin coverings in an effort to hide their shame. The fig leaves failed to cover their nakedness, and did not remove the shame of their sin. Therefore, God "made tunics of skin, and clothed them" (Genesis 3:21). Similarly, modern swimwear (such as women's bikinis and men's swim shorts) does not adequately clothe the body and remove the shame of nakedness. (Notably, in the Scriptures, to "uncover the thigh" means to uncover one's nakedness, Isaiah 47:3.)
Today, people have hardened their hearts toward the shame of their nakedness. They eagerly expose their nakedness by wearing modern-day "fig leaves." Such lack of modesty does not diminish the sin of wearing such shameful attire (Jeremiah 8:12; 1 Timothy 2:9-10). God's word is clear. It is shameful to expose one's nakedness to public view. Reject such immodesty, and keep a sense of shame firmly rooted in your pure and holy heart.