Robert Charles Sproul (1939–2017) was an American Reformed theologian and ordained pastor in the PCA. He founded Ligonier Ministries. This short book Can I Be Sure I’m Saved? (2010) is the seventh in the Crucial Questions series (1983–2019) which includes 31 books (e.g., 1. Who Is Jesus?  . . . 31. How Does God’s Law Apply to Me? ).
Can I be Sure I’m Saved? consists of five chapters. Chapter 1 (The Struggle for Assurance) rightly stresses that we are saved by faith alone but true faith in Christ essentially arouses good works. Chapter 2 (Four Kinds of People) outlines four types of people concerning assurance of salvation, and Chapter 3 (False Assurance) deals with the issue of false assurance that the fourth type of people exhibits. Chapter 4 (Gaining True Assurance) argues that the prescient view of God’s election is the foundation of our assurance. Finally, Chapter 5 (The Source of Full Assurance) encourages the reader by emphasizing that the internal witness of God’s Spirit gives us an “ironclad guarantee of salvation” (p. 71).
This is an accessible book for many as to the notion of assurance of salvation. I especially liked chapter 1 in which Sproul explains the significance of fruitfulness in the believer’s life (Matt 13). True faith is not alone; it essentially brings good works (fruit). Chapter 1 is therefore a succinct antidote to the trendy accusation that magisterial Reformed tradition produces irresponsible and complacent Christians especially because of the doctrines of predestination and perseverance of the saints.
Sproul clearly shows that we can and ought be be sure that we are saved. I agree that we should obtain that assurance “through a diligent pursuit” (p. 45). We should not lose sight, however, of the fact that our assurance is only laid upon what God does: God’s election and the Holy Spirit’s regenerating work.
Allow me to return to Sproul’s questions (p. 64): Do you love Jesus perfectly? Do you love Jesus as much as you ought to? Or do you love Jesus at all? I know that my affection for Jesus is not perfect and yet I know I love him. This book shows that I love Jesus and I know I love him only because I am born again, i.e., I am “changed by the supernatural operation of God the Holy Spirit” (p. 60).
The internal witness of the Holy Spirit continues. What Paul says in 2 Cor 1:21-22 is that God places “his indelible mark on the soul of every one of his people” (p. 70). We are forever sealed for the day of redemption (p. 71).
Now it is God who makes both us and you stand firm in Christ. He anointed us, set his seal of ownership on us, and put his Spirit in our hearts as a deposit, guaranteeing what is to come.2 Corinthians 1:21-22
Sproul writes, “He [God] not only gives us an ironclad guarantee, He seals us for the day of redemption” (pp. 70–71).