Why did God call believers — was it because of their works?
God called believers not because of their works, but according to His own purpose, which is completely wrapped up in His grace. Their calling rests on His will and purpose, not human effort or merit, and it is designed to bring praise to His glory.
Les explains that believers were called not according to their works, but according to His purposes, which are completely wrapped up in the grace of God. He connects this to Ephesians chapter 1, where believers are predestined according to God's purpose, which is under the control of the power of God. Everything is working according to the counsel of His own will. The purpose is that believers should be to the praise of His glory; God gives them breath day after day so that they might bring praise to His glory. Les also references Hebrews, which speaks of offering unto Him the sacrifice of praise, the work of lips, which is praise to God.