The Almighty God has set a measure for everything in the universe, 
both in this world and the hereafter. The prophets are the measure 
for assessing the faith and actions of their communities. In Islamic 
traditions, it is stated that Ali (AS) is the measure of deeds. The 
concept of measure is not exclusive to the hereafter; in the human 
world, too, there is a measure for everything: logic is the measure 
for distinguishing right from wrong thoughts, exams are the measure 
for assessing learners' progress, and thermometers are the measure 
for gauging air temperature. 
The question addressed in this article is: What is the measure for 
assessing the faith of adherents to a religion? How can one 
distinguish a true believer from hypocrites who claim faith, or gauge 
the levels of believers' faith? Although faith is a matter of the heart, 
and only God knows what lies within hearts, the manifestation of 
faith in an individual's actions and personal and social ethics serves 
as a reliable indicator of inner faith. 
The author's claim here is that at least one of the most important 
measures of faith is action. The alignment of faithful actions with the 
religious principles and Sharia of the religion to which the individual 
adheres can serve as a good gauge for their level of faith. By "action," 
we mean both individual devotional acts such as prayer and fasting, as well as personal ethics and behavior, and social actions 
manifested in an individual's ethics, behavior, and social interactions, 
as detailed in religious sources. 
The primary goal of this research is to elucidate the theoretical 
principles of self-assessment in the levels of faith. Secondarily, it can 
provide a solid foundation for field studies and, ultimately, 
contribute to increasing insight and raising public awareness to 
distinguish true believers from those who merely claim faith. As a 
result, forty affirmative and negative components are presented as 
the most important indicators of faith.