Some say, “there is one qualification that proves we are filled with the Holy Ghost … we are living a holy life!”
The quote above proves a necessary condition but not necessarily a sufficient one since,
Beyond Holiness —> in Truth.
More accurately, “truthfully holy”.
There is a type of ‘godliness’ (being holy) which “denies” His Power (especially to Save, e.g. to “Save the World” which is His Will):
“having a form of godliness but denying its power. And turn away from these.” (2 Timothy 3:5)
Only those in “His Truth” don’t deny “His Saving Power”.
Now, it’s also written that the Holy Spirit of God leads into ‘all Truth’ or ‘all things concerning the Lord’ (Helps you ‘remember’ the Knowledge, Wisdom & Understanding especially that of His Revealed Word):
“and the Comforter, the Holy Spirit, whom the Father will send in My name, He will teach you all things, and remind you of all things that I said to you.” – Lord Jesus Christ (John 14:2)
“However, when the Spirit of truth comes, He will guide you into all truth. For He will not speak on His own, but He will speak what He hears, and He will declare to you what is to come.” – Lord Jesus Christ (John 16:13)
As apostle Paul wrote a ‘thing to come’, the Mystery of Christ & the Salvation of the World (‘end’ is God being ‘all in all’, i.e. all creation is filled with Him, that is, perfected in Him):
“that creation itself will be released from its bondage to decay and brought into the glorious freedom of the children of God.” (Romans 8:21)
“how that God was in Christ reconciling the world to Himself, not reckoning their trespasses (the world’s sins) to them, and having put into us the word of reconciliation.” (2 Corinthians 5:19)
“and through Him (Lord Jesus Christ) to reconcile all things to Himself, having made Peace through the Blood of His Cross; through Him, I say, whether things on earth or things in the heavens.” (Colossians 1:20)
“When all things are subjected to Him, then the Son Himself also will be subjected to the One who subjected all things to Him, so that God may be all in all.” (1 Corinthians 15:28)