Hadeeth Qudsi 24:

On the authority of AbuHurayrah (may Allah be pleased with him), who said that the Messengerof Allah   said:

If Allah has loved a servant [ofHis] He calls Gabriel (on whom be peace) and says: I love So-and-so,therefore love him. He (the Prophet peace be upon him) said: So Gabrielloves him. Then he (Gabriel) calls out in heaven, saying: Allah lovesSo-and-so, therefore love him. And the inhabitants of heaven love him.He (the Prophet peace be upon him) said: Then acceptance is establishedfor him on earth. And if Allah has abhorred a servant [of His], Hecalls Gabriel and says: I abhor So-and-so, therefore abhor him. SoGabriel abhors him. Then Gabriel calls out to the inhabitants ofheaven: Allah abhors So-and-so, therefore abhor him. He (the Prophetpeace be upon him) said: So they abhor him, and abhorrence isestablished for him on earth.

It was related by Muslim (alsoby al-Bukhari, Malik, and at-Tirmidhi).