"It is narrated by Mu‘ādh bin Jabal that he heard the Messenger of Allāh (صلى الله عليه وآله وسلم) saying:

   Allāh the Exalted and Almighty said: ‘My love has been made obligatory for those two persons who love each other on My count and spend time together for My sake, and see each other for My sake and give money to each other generously for My sake.’"

This sahīh (sound) hadīth narrated by Mālik bin Anas in al-Muwattā, b. of sha‘ar (hair) ch.5 (2:954#16), and Ibn ‘Abd-ul-Barr said its chain is good. Ahmad bin Hambal also transmitted it in his Musnad (5:233); Hākim in al-Mustadrak (4:169), who graded it sahīh, and also confirmed by Dhahabī; Baghawī in Sharh-us-sunnah, (13:49-50#3463); Khatīb Tabrīzī in Mishkāt-ul-masābīh, b. of ādāb (good manners) ch.16 (3:75#5011). [src: Ch3 of Beseeching for Help, Tahir-ul-Qadri]

Narrated by Ubayy ibn Ka'b (Radi Allah Ta'lah Anhu): "I said: Allah's Messenger (Sal-allahu-aleihi-wasallam), I invoke blessings upon you very frequently. How much of my supplication should I devote to you. He said: As much as you like. I said: May it be a quarter? He said: As much as you like, but if you increase it, it will be good for you. I said: May it be a half? He said: As much as you like, but if you increase it, it will be good for you. I said: May it be two thirds? He said: As much as you like but if you make an increase in it, it will be better. I said: May I devote the whole of my supplication to you (that I make in my prayer)? Thereupon he said: In that case it will take care of you and your sins would be expiated."

Tirmidhi transmitted it. Hadith No. 929 of Mishkat al-Masabih. [src: road-to-heaven.com]