yes - that phrase can mean that church attenders who did not commit to God left the faith - just like people dating can break up even though they were never married - they were both dabbling without making commitment - and before they made a commitment they left/fell away/departed/broke up/etc
someone who is not married will depart from their marriage?
Someone who is not really saved, will depart from the faith, by which they are saved?
Here is the definition of “the faith”.
Our common faith in Jesus Christ.
Scripture teaches we are in a common “household of faith” as family.
Therefore, as we have opportunity, let us do good to all, especially to those who are of
the household of faith.
Galatians 6:10
Scripture texts -
Beloved, while I was very diligent to write to you concerning
our common salvation, I found it necessary to write to you exhorting you
to contend earnestly for the faith which was once for all delivered to the saints.
Jude 1:3
Examine yourselves as to whether you are
in the faith. Test yourselves. Do you not know yourselves, that Jesus Christ is in you?—unless indeed you are disqualified.
2 Corinthians 13:5
There is no mention of people attending Church.
You are creating a narrative that doesn’t exist in the scripture we are discussing.
Paul is using a term that was common to him and others in the first century.
The term “the faith” refers to those within the faith of Jesus Christ, and its all its uses doesn’t refer to people who attend Church who may or may not be saved.
If a person is in the faith, our common faith in Christ, a part of the household of faith, then later on the give heed to doctrines of demons, by which the depart from the faith, (by transgressing the doctrine of Christ) then they have departed from the common salvation through faith in Christ.
Depart from means to desert, or withdraw from.
A person in the army who deserts the army, has willing revolted and withdraw himself from the army.
Strong’s Definitions
ἀφίστημι aphístēmi, af-is'-tay-mee; from
G575and
G2476; to remove, i.e. (actively) instigate to revolt; usually (reflexively) to desist, desert, etc.:—depart, draw (fall) away, refrain, withdraw self.
KJV Translation Count — Total: 15x
The KJV translates Strong's G868 in the following manner: depart (10x),
draw away (1x),
fall away (1x),
refrain (1x),
withdraw self (1x),
depart from (1x).
This doesn’t refer to people who were never in the faith.
If a person does not continue this n the the faith, how can they still have salvation through faith?
strengthening the souls of the disciples, exhorting them to
continue in the faith, and saying, “We must through many tribulations enter the kingdom of God.” Acts 14:22
again
Whoever transgresses and does not abide in the doctrine of Christ does not have God. He who abides in the doctrine of Christ has both the Father and the Son. 2 John 9
We are called to continue in the faith.
JLB