What is the authenticity of the two narrations attributed to Umar ibn Abd al-Aziz concerning gradualism in the implementation of Sharia rulings, and can what is stated therein be considered a legitimate ijtihad (independent reasoning) that may be emulated?

Lenience in applying Sharia does not permit the forbidden; rather, it is a gateway to gradualism and considering circumstances. What is based on the measure of ability and inability is accepted, for obligations are waived when impossible. What can be implemented without a predominant corruption must be done immediately, unlike what one cannot do or what leads to corruption. This is supported by the statement of Umar ibn Abd al-Aziz to his son: "I fear that I might impose the truth upon people all at once, and they reject it all at once," and "I did not feel safe that they would tear a rift upon me in which much blood would be shed." Al-Shatibi mentioned this narration, using it as evidence for considering ability and not burdening the accountable person with what causes them weariness or disrupts the well-being of their worldly life.