There are two ultimate expressions of God’s will in Scripture. The first is our salvation: “This is good, and pleases God our Savior, who wants all men to be saved and to come to a knowledge of the truth” (1 Tim. 2:3-4). The second is related: “It is God’s will that you should be sanctified” (1 Thess. 4:3a). Both of these were accomplished by Jesus Christ. “It is because of him that you are in Christ Jesus, who has become for us wisdom from God—that is, our righteousness, holiness and redemption” (1 Cor. 1:30).
So we know that the will of God for us is our salvation, which includes our justification (conversion), holiness (sanctification), and the redemption of our bodies at the Second Coming (again, all paid for in advance).
Since we have already experienced our justification, and we wait patiently for the Second Coming, our participation now is in our holiness (our sanctification). Remember that it is already paid and provided for.
His divine power has given us everything we need for life and godliness through our knowledge of him who called us by his own glory and goodness. (2 Pet. 1:3)Being in the will of God means obedience to His clear commands in the Scriptures.
But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control. Against such things there is no law. Those who belong to Christ Jesus have crucified the sinful nature with its passions and desires. (Gal. 5:22-24)
Knowing the details of God’s will outside of obeying Scriptural commands (for questions like, “Who should I marry? Where should I work? Should I be a missionary?”) is not difficult if we are walking in the light, walking in the Spirit. If I am not walking in the light, the detailed will of God could be written on the wall, and I would not be able to read it.