Is the statement that faith increases but does not decrease, and the statement that faith increases and decreases, both considered among the permissible differences of opinion among the people of Sunnah?

The doctrine of Ahl al-Sunnah wa al-Jama'ah and the creed of the Saved Sect is that faith increases and decreases. This has been indicated by texts from the Quran and the Sunnah, and by the consensus of the scholars. The assertion that faith increases necessitates the assertion that it decreases, as Sufyan ibn Uyaynah mentioned. Some early scholars, such as Imam Malik, initially hesitated to use the term "decreases" due to the absence of an explicit text in the Quran, but he affirmed variations in faith, and later explicitly stated that faith increases and decreases. The correct position is to affirm both increase and decrease, which is what the texts of the Quran and Sunnah indicate. As for denying increase or decrease, that is among the sayings of the people of innovation, whereas hesitating to use the term "decrease" while affirming increase and variations was an ijtihad (independent reasoning) from some of Ahl al-Sunnah, and it was later confirmed that they explicitly stated decrease. Furthermore, disbelief is not limited to a decrease in faith or its complete disappearance; rather, it includes disbelieving statements, actions, and beliefs.