Brachos 7b: Do not compete with Resha'im or be envious of their deeds. Also "Al Tischar ba'Mere'im Al Tekanei b'Osei Avlah" means like this; one may confront Resha'im in this world.

Rashi: Do not envy their success, to be a Rasha like them. Malbim - Kin'ah followed by a noun with the prefix Beis is envy of another's attribute, and desire to be like him. He tells his son, even if you see sinners succeeding in this world, do not desire to be like them.

R. Yonah: Do not envy the Resha'im's serenity, wealth and grandeur.

Orchos Tzadikim (Sha'ar ha'Kin'ah DH Ach): When a person envies sinners, and sees their wealth and success, and sees Tzadikim waxing poor and afflicted, his Nefesh despises Yir'as Hashem and his Mishpatim and Chukim, and he despise those who learn Torah and fulfill it.

R. Yonah: You should envy only Yir'as Hashem, and yearn for it the entire day. This is an obligation of a Tzadik. Thoughts of Yir'as Hashem should not depart from Hashem. The envy and desire is to reach perfection. One should not slacken from this from the morning until the evening.

Orchos Tzadikim (Sha'ar ha'Kin'ah DH Af Al Pi): This is the Midah of Elyonim, to put his Kin'ah on Yir'as Shamayim,

Malbim: You should have Kin'ah for Yir'as Hashem, and desire to have deeds like those of Yir'ei Hashem. This envy should nest in his heart the entire day. The Midah of Kin'ah is bad when it is of Resha'im, and good when it is of Yir'as Hashem. A Chacham Lev uses it only on the good side.