Eminent Sahabi (Noble Companion of Beloved Prophet ﷺ), Hazrat Abdullah ibne Mas’ood (RA) said:
Assess your heart in three occasions:
One: When you listen to the Qur’an
Two: At the Majlis (gathering) of Allah’s Zikr, i.e. while listening to Deeni lectures/bayan, attending Taleem.
Three: While engaged in Allah’s Zikr in solitude
If in case you do not find your heart present (i.e. if in none your mind gets set and not attracted towards) in three situations mentioned, do pray to Allah Taala that He may, by His Mercy, provide at least one heart to you; because, you have no heart.
Note: If one doesn’t find any attraction in the mentioned situations, it doesn’t mean that one has no Iman or s/he should stop doing the good deeds mentioned. Rather, often ‘no attraction’ in Ibadat is a test for the servant of Allah (this has been clarified by Pious Scholars while discussing about taste/attraction in Ibadat; remember, taste is not the objective of Ibadat. See the article: No Taste in Worship: Taste vs Test in this site)
The saying of Hazrat Abdullah ibne Mas’ood (RA) provides an easy means to look into the condition of one’s Iman by oneself; it is a scale to simply assess oneself – how his Iman is, because, the mentioned occasions (recitation of the Quran, listening to Allah Taala’s Words and getting engaged in Allah Taala’s remembrance in solitude) are such that most believers’ hearts find a general appeal to those. Therefore if someone (a believer) is deprived of this minimal appeal, he is asked to make dua to Allah Taala and request at least ‘one heart’.