APATHY: Lack of interest or concern especially regarding Scripture. In the believer, apathy occurs when we choose to think independently of God. When this occurs, sins go unconfessed. The result is carnality or carnal thinking and activities, (worldliness).
When the believer is carnal (out of fellowship) the believer acts and thinks just like the unbeliever. Continuous sin and prolonged indifference (apathy) causes scar tissue to build up on the soul, which causes hardening of the heart. In extreme conditions this leads to the sin unto death, when God can no longer use the believer because of maximum negative volition.
When the believer is in carnality, he/she is “grieving and quenching the Holy Spirit.” Quenching the Spirit is the absence of the Holy Spirit’s mentorship. Grieving the Holy Spirit is the absence of the empowerment of the Holy Spirit.
Apathy is living in the flesh — controlled by the flesh, as in addictions and lust-patterns. Apathy is human-viewpoint thinking. Apathy is indifference to the call (conviction) of the Holy Spirit (quenching). Apathy is thinking independently of God, which was actually the first sin of Satan, the fallen angels who sided with Satan, and Eve, and Adam. Apathy is literally a repeat of the original sin so that all mankind is guilty of rejecting God in favor of self-rule.
Please note: In the Church Age we have a new commandment that replaces the Mosaic Law: “Be (keep on being) filled with the Spirit” (Ephesians 5:18 cf., Matthew 22:6_40; Galatians 5:22-23).
Spirituality and carnality are absolutes (Ephesians 4:30; 1 Thessalonians 5:19; 1 John 1:7; 2:10; 3:49). The believer is either spiritual (filled with the Spirit — in fellowship, controlled by the Holy Spirit) or carnal (out of fellowship, controlled by your sin nature — the flesh — quenching and grieving the Holy Spirit). When the believer is filled with the Holy Spirit, the Holy Spirit produces Divine Good through you, and Jesus Christ is glorified. When the believer is carnal/out of fellowship, he/she produces human good. Spirituality and carnality are basic concepts of experiential Christianity.
Happy Studying!
The preceeding explanations are reproduced here, from RBT Bible Ministries’ book “OLD SIN NATURE vs. THE HOLY SPIRIT” (used with permission).