You are right, the Bible doesn't suggest eternal security...it explicitly states it haha. Here are merely a few examples:
John 6:37
"All that the Father gives me will come to me, and whoever comes to me I will never cast out."
John 6:39-40
"And this is the will of him who sent me, that I should lose nothing of hall that he has given me, but raise it up on the last day. For this is the will of my Father, that everyone who looks on the Son and believes in him should have eternal life, and I will raise him up on the last day.”
John 6:47
"No one can come to me unless the Father who sent me draws him. And rI will raise him up on the last day. 45 It is written in the Prophets, s‘And they will all be taught by God.’ uEveryone who has heard and learned from the Father comes to me— 46 not that anyone has seen the Father except he who is from God; he has seen the Father. 47 Truly, truly, I say to you, whoever believes has eternal life."
Romans 8:38-39
"For I am sure that neither death nor life, nor angels nor rulers, nor things present nor things to come, nor powers, nor height nor depth, nor anything else in all creation, will be able to separate us from the love of God in Christ Jesus our Lord."
Romans 11:29
"For the gifts and the calling of God are irrevocable. "
Ephesians 1:12-14
"In him we have obtained an inheritance, having been predestined according to the purpose of him who works all things according to the counsel of his will, so that we who were the first to hope in Christ might be to the praise of his glory. In him you also, when you heard the word of truth, the gospel of your salvation, and believed in him, were sealed with the promised Holy Spirit, who is the guarantee4 of our inheritance until we acquire possession of it, to the praise of his glory."
2 Corinthians 1:22
"And who has also put his seal on us and given us his Spirit in our hearts as a guarantee."
Philippians 1:6
"And I am sure of this, that he who began a good work in you will bring it to completion at the day of Jesus Christ."
Again I also point you to the Canons of Dort which addresses this soteriological issue.
Thanks for sharing the article. I will read it when I have a availability and try to respond further.