If you were living in the Old Covenant, before the Work of the Cross, only
some of what Dan Corner (a rabid conditional security guy) writes in his article would hold true.
But we don't.
We live in the era of the New Covenant, AFTER the Work of the Cross.
We don't forgive to receive forgiveness, but we forgive because we are forgiven:
Before the Cross:
14 For if you forgive other people when they sin against you, your heavenly Father will also forgive you. 15 But if you do not forgive others their sins, your Father will not forgive your sins. (from Mt. 6)
After the Cross:
32 Be kind to one another, tenderhearted, forgiving one another, as God in Christ forgave you. (from Eph. 4)
13 bearing with one another and, if one has a complaint against another, forgiving each other; as the Lord has forgiven you, so you also must forgive. (from Col. 3)
Note that there are no verses after the Work of the Cross that require that we forgive to be forgiven - we are forgiven when we believe in Christ - that is what makes salvation possible, and is the first element of salvation. Next comes the gift of God's Righteousness given to us in Christ, then New Life, sealed with the Holy Spirit. These things all happen simultaneously when one puts their faith in Christ Jesus.
The forgiveness we receive when we believe in Christ is not conditional on our forgiving others. Forgiving others, however, often is a very real fruit that happens when we come into Christ.
As Ephesians and Colossians show us, forgive AS you have BEEN FORGIVEN, not forgive IN ORDER to be forgiven.
Even the Colossians passage, which says, "so you must also forgive" does not follow it up with an "or else", but talks of Fruit of the Spirit type stuff, not eternal damnation if you don't forgive someone. Please don't misunderstand - forgiving one another is a GOOD thing - it is the RIGHT and HEALTHY thing to do, but your salvation does not hang on whether or not you do it.
-JGIG