What does the Bible teach about believers being called holy?

In the sermon, it is stated that believers, referred to as 'holy brethren,' possess holiness not based on their feelings or actions but because they are sanctified in Christ. This union with Christ imparts His perfect righteousness to them, making them as holy as God in His sight. This incredible truth emphasizes that salvation is a work of God’s grace, casting any reliance on personal merit aside. It reassures believers that regardless of their daily struggles, they stand holy before God because of their identity in Christ, which is foundational to their faith and assurance of salvation.