A Christian must stand in the grace of God (Romans 5:2). He must be
strong in the grace of God. "You therefore, my son, be strong in the
grace that is in Christ Jesus." (2 Timothy 2:1). The Scripture says
plainly that is is "good that the heart be strengthened [or established]
with grace" (Hebrews 13:9). "Finally, my brethren, be strong in the
Lord and in the power of His might. Put on the whole armour of God, that
you may be able to stand against the wiles of the devil." (Ephesians
6:10,11).
All the armour of God is received by the grace of God. We did
not pay for the "breastplate of righteousness" or "the shield of faith"
or any other parts of that armour. It is therefore by drawing on the
grace of God that we are going to be able to resist temptation and stand
against all the temptations and trials that Satan wants to discourage
us with and make us fall, if possible.