Romans 12:2 (CSB) 2 Do not be conformed to this age, but be transformed by the renewing of your mind, so that you may discern what is the good, pleasing, and perfect will of God.

In my bible I have underlined Romans 11:21-22 and linked it with Romans 12:1-2. Why? Romans 11 talks about God's severity and kindness and Romans 12 talks about conforming and transforming. If we want God's severity in our lives then by all means we can be conformed to this present age. But if we want God's kindness then we must be transformed! Transformed in our actions, yes, but even more transformed in our thinking. Whatever we spend our time thinking about that is what we will do and become! So how do we transform our minds? Through the washing of the word of God (Titus 3:5, Ephesians 5:26). That is done through hearing, reading, studying, memorizing, and meditating on the word of God. Then we will be able to discern what is the Good, Pleasing, and Perfect will of God! (Romans 10:17, Revelation 1:3, Acts 17:11, Psalm 119:9,11, Psalm 1:2-3)

Romans 11:21-22 (CSB)  21 because if God did not spare the natural branches, he will not spare you either. 22 Therefore, consider God's kindness and severity: severity toward those who have fallen but God's kindness toward you -- if you remain in his kindness. Otherwise you too will be cut off.