Isaiah 32:17 The work of righteousness will be peace, And the effect of righteousness, quietness and assurance forever. (NKJV)
Being assured of your salvation has many facets. There is no simple checklist or magic formula. The Bible does however say that we can KNOW we are saved:
1 John 2:3 Now by this we know that we know Him, if we keep His commandments. (NKJV)
The book of 1John discusses many aspects of the assurance of salvation. Obedience is a common thread in showing our love for God and demonstrating our truly reborn spirit.
The “work of righteousness” could be summed up by obedience in all things Godly. Righteousness produces peace. How? By revealing sin and replacing it with holiness. Righteous is Godly light that always exposes the darkness of sin. The pursuit of righteousness is the life of a Peacemaker that Jesus speaks about in the Beatitudes (Matt 5). This peace does not always come “peacefully” because sin must be slain first; and it does not depart with ease or cooperation.
Matthew 5:9 Blessed are the peacemakers, For they shall be called sons of God. (NKJV)
The infusion of righteousness produces peace. The effect of righteousness is quietness and assurance. The “quietness” is akin to the meekness Jesus also spoke of in the Beatitudes. Meekness is calm, supreme confidence and control produced by the Holy Spirit. It is the gentle, supernaturally confident attitude that comes from trusting the Holy Spirit to guide us; allowing us to be unmoved by our external circumstances.