Art class is probably the best place to overcome lust because you have to observe the human body while focusing on the task at hand. You don't have time to lust if you want to get the assignment done, so you have to train yourself to not think about those things while you are working. And the ultimate issue is what is going on in your heart and mind, not what you are seeing. The ultimate test of self-control and walking in the Spirit is being able to see a nude without automatically responding with lustful thoughts, and you can't get there by constantly avoiding the external stimulus. Note what Jesus says about the origin of sin and what defiles us in Matthew 15: defilement doesn't come from external things that we may be exposed to, but it comes from our hearts. The focus should all be on what we think in our hearts, and not on what we are seeing or exposed to. Focusing on the external only leads to legalism.
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10 Jesus called the crowd to him and said, “Listen and understand. 11 What goes into someone’s mouth does not defile them, but what comes out of their mouth, that is what defiles them.”
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15 Peter said, “Explain the parable to us.”
16 “Are you still so dull?” Jesus asked them. 17 “Don’t you see that whatever enters the mouth goes into the stomach and then out of the body? 18 But the things that come out of a person’s mouth come from the heart, and these defile them. 19 For out of the heart come evil thoughts—murder, adultery, sexual immorality, theft, false testimony, slander. 20 These are what defile a person; but eating with unwashed hands does not defile them.”
(Matthew 15:10-11, 15-20)