Dahhak bin Qays reported,
The Messenger of Allah ﷺ said, "Allah says, 'I am the best of partners. Whoever associates anyone with Me, that deed belongs to the one he associated with Me.' People, devote your deeds sincerely to Allah, for Allah 
accepts only those deeds done purely for Him. Do not say, 'This is for Allah and for kin,' for it will go to the kin and nothing of it will be for Allah. And do not say, 'This is for Allah and for your honor,' for it will go to your honor and nothing of it will be for Allah ."
Azami 14989
Hasanعن الضحاك بن قيس قال
قال رسول الله ﷺ: إن الله يقول: أنا خير شريك، فمن أشرك بي أحدا فهو لشريكي، يا أيها الناس، أخلصوا الأعمال الله، فإن الله عز وجل لا يقبل من العمل إلا ما خلص له، ولا تقولوا: هذا لله وللرحم، فإنه للرحم، وليس لله منه شيء، ولا تقولوا: هذا الله ولوجوهكم، فإنه لوجوهكم، وليس الله عز وجل منه شيء.
No references are available.
Ibn Qani related it in Mujam Sahaba (473) from Ahmad bin Yahya bin Ishaq, who said, "Saeed bin Sulayman told us, from Ubayda bin Humayd, from Abdul-Aziz bin Rafi, from Tamim bin Salama, from Dahhak bin Qays," who said, and then he mentioned it. Its chain is hasan because of Ubayda bin Humayd Kufi, for his hadith is hasan.Bazzar related it in Kashf Astar (3567), and Daraqutni in his Sunan (133), both of them through Ibrahim bin Mujashir, who said, "Ubayda bin Humayd told us," with the same wording, except that he said "Tamim bin Tarafa" instead of "Tamim bin Salama." Ibn Adi said of Ibrahim bin Mujashir that he has unrecognized reports through chains of transmission that are not preserved. This is as he said, for he contradicted Saeed bin Sulayman, who is Dabbi, Abu Uthman Wasiti, and who is among the trustworthy, retentive scholars.As for his statement, "the best of partners," it means that Allah the Exalted does not accept a deed in which someone else was made a partner with Him. Rather, He gives it over and leaves it entirely to that partner, so there is no reward and no recompense for it with Allah .