Salvation cannot be earned; it is indeed a pure gift. But it can be lost through sin. Both Jesus and Paul warn of this. This is the true teaching of the Bible.
Salvation IS a gift but it can be lost thru sin? Soooo...you have to earn it back?
To follow up on my prior post.
Staying in Ephesians but going back to Ephesians 1:13-14
13In Him, you also, after listening to the message of truth, the gospel of your salvation— having also believed, you were sealed in Him with the Holy Spirit of promise,
14who is given as a pledge of our inheritance, with a view to the redemption of God’s own possession, to the praise of His glory.
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The highlighted words in above are very important in understanding the security of the believer.
The words in red indicate an action by the individual.
It is incumbent upon us to hear the word and then also believe.
These verbs are both aorist, participle, active. The aorist indicates an action that is undefined; it is an action that has occured
These would be described as adjectival participles in that they are modifying a noun..in this case the individual.
The word bolded in black is an aorist, indicative, passive verb.
The aorist has already been explained.
The use of the indicative means the author believes this to be true.
Now here's the key....the tense of this verb is passive.
This means the action of the verb on the subject of the verb is from an outside force....in this case God.
Paul is saying the person who has heard and believed the gospel is sealed with the Spirit of promise.
IT IS GOD WHO DOES THE SEALING.
Paul notes this in two other places in the Bible.
Ephesians 4:30 and 2 Corinthians 1:22.
There are no verses in the New Testament indicating the believer can ever unseal nor unseals what God has sealed.
Salvation is not earned by works and it's not kept by works.
It's given and that's that, sin notwithstanding.