The Satan sends detachments of his own in order to put people to trial and the highest in rank, in his eyes, is one who is most notorious in sowing the seed of dissension.
Sahih Muslim Book 52, Hadith 61
← Previous Hadith Iblis places his throne upon water; he then sends detachments (for creating dissension) ; the nearer to him in rank are those who are most notorious in creating dissension. One of them comes and says: "I did so and so." And he says: "You have done nothing." Then one amongst them comes and says: "I did not spare so and so until I sowed the seed of discord between a husband and a wife." The Satan goes near him and says: "You have done well." A'mash said: He then embraces him.

Sahih Muslim Book 52, Hadith 60 Next Hadith → There is none amongst you with whom is not an attache from amongst the jinn (devil). They (the Companions) said: Allah's Messenger, with you too? Thereupon he said: Yes, but Allah helps me against him and so I am safe from his hand and he does not command me but for good.

Sahih Muslim Book 52, Hadith 62