Envy.

Envy "But if you are bitterly jealous and there is selfish ambition in your heart, don't cover up the truth with boasting and lying.(NLT)" -James 3:14

"Envy is one of the seven deadly sins because it plants a root of bitterness in our hearts. Envy tells us that either we aren't good enough and deceives us into believing that our worth is measured by a certain level of accomplishment. You are valuable because you are God's one-of-a-kind creation! Your worth is not measured by something you can do but is given to you by God. Avoid envy and the places that it likes to slip into your life. "