God never leaves us alone! And, even though He, as the Holy Spirit, is ALWAYS with us, He has given us Armor to use to fight the battles we will encounter. The Bible tells us in Ephesians 6:10-13:
"(10) Finally, my brethren, be strong in the Lord and in the power of His might. (11) Put on the whole armor of God, that you may be able to stand against the wiles of the devil. (12) For we do not wrestle against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this age, against spiritual hosts of wickedness in the heavenly places. (13) Therefore take up the whole armor of God, that you may be able to withstand in the evil day, and having done all, to stand."