The scriptures you are using relate generally, and some specifically, have to do with those caught in a known sin, and knowing it. In fact, there is a three step process described in the New Testament for dealing with those who HAVE KNOWN God but are sinning.
There is no straight line between your point and the scriptures you have presented. We are to go where the sinners are, and there are very few concrete and defined reasons for not doing that.
Let me say it again: Visiting unsaved friends is one thing. Regularly attending their unholy assemblies (instead of attending a gathering of saints/believers) in something very different. And we are commanded not to do this -- being unequally yoked with unbelievers. This precisely what 2 Corinthians 6:14-18) is talking about.
We are to go where the sinners are, and there are very few concrete and defined reasons for not doing that.
Here is the Biblical approach: My church goes out several times a week to knock on doors and share the gospel with the unsaved. See Luke 10 where Jesus sends out his disciples in pairs "as lambs among wolves" in the highways and hedges to preach the gospel to the unsaved.
We don't "worship" with Mormons in order to share the gospel with them. We do walk their neighborhoods and knock on their doors and share the gospel with those willing to listen, which unfortunately is few.
John Wesley...
If he did in fact embrace Arminianism, if he did believe that one can lose his/her salvation, then he was not trusting in the finished work of Jesus Christ on the cross to save him, but was conditioning his salvation on his own works in some part so as not to lose his salvation. That is NOT the gospel. And only the gospel saves. There is no way to soft peddle this. Salvation is a gift received by grace through faith, not of works. (Ephesians 2:8,9).
"As many as received him (Jesus) to these he gave the power to become the sons of God, even to them that believe on his name." (John 1:12) [Once sons always sons.]
"Verily, verily, I say unto you, He that heareth my word, and believeth on him that sent me, hath everlasting life, and shall not come into condemnation; but is passed from death unto life." (John 5:24) [no future condemnation, but life, eternal life right now at the moment of belief]
"Jesus said unto her, I am the resurrection, and the life: he that believeth in me, though he were dead, yet shall he live: And whosoever liveth and believeth in me shall never die. Believest thou this?" (John 11:25,26) [Those who believes shall never die. Never be subjected to the 2nd death explained in Rev 20, 21.
I've heard all the verbal aspects games, that, "You must keep believing." The command in Acts 16:31 [believe -- pisteuson] is perfective in aspect (aorist), a one time event. One can fall away and not lose his/her salvation. One doesn't become unborn again.
Arminianism, Holiness Movement, Pentacostalism all teach a different gospel. They are all ultimately works-reliant. The Bible says something quite different:
"In whom ye also trusted, after [that] ye heard the word of truth, the gospel of your salvation: in whom also after [that] ye believed, ye were sealed with that holy Spirit of promise, Which is the earnest of our inheritance until the redemption of the purchased possession, unto the praise of his glory." (Ephesians 1:13,14) <> When we believe, we immediately receive the holy Spirit of promise. We are born again at that moment. It is the "earnest" (the promise of assurance) of our future inheritance which we shall receive when we are resurrected as His purchased possession. And no one can snatch us out of the Father's hand. No one, not even ourselves.
Anyone who thinks he can lose his salvation has NOT trusted Christ to save him, but is still holding on to "works" in some ultmately damning capacity, however small.
Believest thou this? Have you trusted in Christ alone to save you?