What is the ruling on advising an envious person in a harsh manner that might hurt him, especially if he is a relative, and does that displease Allah Almighty?

The original principle in the method of giving advice is that it should be according to the situation of the advisee, whether with gentleness or strictness. If the situation of the one being called [to Allah] necessitates harshness in speech so that he may be deterred, then there is no objection. And advice to the questioner: always assume the best of Muslims and be cautious in leveling accusations against people.