Assurance of Salvation and Evanescent Grace

True assurance of salvation is found by resting in the truth of God’s grace and the certainty of His promise, rather than in the shifting strength of our own performance. While it is true that believers may fall into grievous sins or experience periods of spiritual dryness where their graces and comforts seem diminished, these experiences do not undo the reality of the covenant of grace [1].

The reformers often pointed out that the comfort of a doubting soul relies entirely on the stability of God's promise [3, 5]. If our assurance were dependent on our own ability to avoid falling away, we would be left in a state of constant anxiety [3, 5]. Instead, we are encouraged to look to the "truth of grace" rather than the "degree of grace" [4]. Even the smallest, weakest measure of true faith, because it is the fruit of the Spirit, is a diamond of great price that serves as a ground for assurance [4].

Richard Sibbes highlights that we must labor to maintain this assurance because it is the very engine of Christian life; without knowing that Christ is ours, we cannot perform the basic duty of thankfulness [6]. Assurance is not a matter of looking inward at our own perfection, but of resting in the fact that God justifies the ungodly by imputing Christ’s righteousness to them, not by anything they have done [1].

For context, James Arminius offers a different perspective on this certainty: while he also affirms that a believer can be persuaded of their standing as a child of God through the work of the Spirit and the fruits of faith, he is more cautious, noting that he does not place this assurance on the same level of objective certainty as the knowledge that God exists or that Christ is the Savior of the world [2].