Say (O Prophet ﷺ), ‘If you love Allāh, then follow me. Allāh will love you and forgive you, your sins. And Allāh is the Most-Forgiving, Very-Merciful.’ Say, ‘Obey Allāh and the Messenger.’ Then should they turn back, Allāh does not love the disbelievers. [Quran, Surah Imran (3), verse 31-32]
Affirmed in these verses is the belief in the Messenger as well as the need to follow the Messenger ﷺ so that we stand informed that the rejection/refusal to obey the Prophet ﷺ is an act of disbelief.
Love is something secret. Whether or not a person loves another person, or loves less or more, are questions which cannot be answers precisely. There is no measure to determine the truth of the matter except that one makes an educated guess based on visible conditions and dealings, for love leaves traces and signs which could help in recognising it as such. Now, in these two verses, Allah ﷻ, tells those who claimed that they love Allāh and hoped to be loved by Him (ﷻ), above is the real criteria of His (ﷻ) love. In other words, if a person living in this world today claims that he loves his Creator then he must test it on the touch-stone of his obedience to the Messenger of Allāh ﷺ, that is to match it against the frequency and quality of where and how he has been following the Messenger ﷺ. How true a person turns out to be in his claim will be visible from how much he makes it a point to follow the Noble Messenger ﷺ. Using the guidance brought by him ﷺ (the Sunnah), as the guiding force in his life.
Rasūlullāh ﷺ has said: He who has obeyed Muḥammad ﷺ, has obeyed Allāh. And he who has disobeyed Muḥammad ﷺ, has disobeyed Allāh.