Summary: Nothing can hinder the Lord.
Paul writes to the church at Corinth that “we live by faith not by sight” (2 Corinthians 5.7). This simple aphorism, often set forth as the litmus test for Christian living, is easily misused. On the one hand, it may be limited to the doctrinal content of salvation; on the other, faith may be conceived as a prosaic justification for doing what one wants. A biblical application of “living by faith” ought to reflect a balanced understanding of God’s covenant purposes for His people. “Living by faith” ought never to be an excuse for doing what one wants – unless, of course, what one wants is to delight himself in the Lord (Psalm 37.3-6). Living by faith is action predicated on the known will of God. The story of Jonathan and his armor bearer fighting the Philistines at Micmash is model for this kind of faith.
Before one can presume to live out his or her faith there must be some understanding of what it means to be saved by faith. The reformation understanding of salvation is predicated upon a doctrine of justification that comes by way of grace alone, through faith alone, because of Christ alone. Christ’s righteousness is imputed to the elect of God because the perfect justice of God was satisfied by the perfect work of Christ. Such justification is not grounded on any merit rooted in the recipient of grace, nor is it based on an infusion of Christ’s righteousness; rather, its genesis is in God who in the person of His Son provides salvation to all who put their trust in Him.
Being saved by faith means one is rescued from the affects of sin; this includes guilt (Ephesians 1.7; Colossians 1.14), pollution (Romans 6.6, 17; 7.21-25a), slavery (Romans 7.24-25; Galatians 5.1), alienation from God (Ephesians 2.12), an Adamic nature that is subject to the wrath of God (Ephesians 2.3), and everlasting death (Ephesians 2.5-6). Positively stated, it brings men into a state of: righteousness (Romans 3.21-26, 5.1), holiness (Romans 6.1-4; 12.1-2), freedom Galatians 5.1; 2 Corinthians 3.17; and blessedness which includes: fellowship with God (Ephesians 2.13), the love of God (Romans 5.5), and everlasting life (Ephesians 2.1, 5; Colossians 3.1-4).
While faith in the Lord Jesus Christ is the cornerstone of salvation and a right doctrinal understanding of this faith is vital, there is more to faith than this. Indeed, a proper theology requires an orthopraxy. The true believer is a part of the covenant community of faith, a community that lives out the implications of its faith. Consider Paul’s admonition to the Philippians: Therefore, my dear friends, as you have always obeyed – not only in my presence, but now much more in my absence – continue to work out your salvation with fear and trembling, for it is God who works in you to will and to act according to his good purpose (Philippians 2.12-13). Why live this way? Because the doctrine of the incarnation demands it.
That Jonathan understands the unique covenant relationship between Israel and Yahweh is evident in his identifying the Philistines as “those uncircumcised fellows.” It is the same term of reproach used by David in his description of Goliath (1 Samuel 17.26, 36). Jonathan understands that Israel belongs to God (Exodus 19.5-6) and this reality requires action that supports such a faith. Jonathan understands and acts on a biblical principle that few people practice: it is God who fights for us, that is, He protects the believers within the shelter of His divine providence (cp. Luke 13.34). This principle is everywhere evident in Scripture. For example, Isaiah writes: I will lead the blind by ways they have not known, along unfamiliar paths I will guide them; I will turn the darkness into light before them and make the rough places smooth. These are the things I will do; I will not forsake them (Isaiah 42.16; cp. 40.4; 45.2). Paul is his summary statements to the church at Thessalonica writes: May God himself, the God of peace, sanctify you through and through. May your whole spirit, soul and body be kept blameless at the coming of our Lord Jesus Christ. The one who calls you is faithful and he will do it (1 Thessalonians 5.24 [emphasis mine]).