The dividing line and problem in this thread is a basic misunderstanding of theology on both sides. Some are accusing others of teaching “having to hold onto Christ” which is countered with the fact Christ holds onto us, John 10:28 for example.
Thus that we hold onto Christ (faith) is prematurely tossed out as “works salvation.” Remember that Paul stated he had kept the faith in 2 Timothy 4:6-8. This of course was by God’s grace in the work of sanctification.
Note that what we are talking about here isn’t salvation at all, it is sanctification. The holding onto Christ scenario has nothing to do with being justified (salvation) but has to do with sanctification, perseverance or preservation of the saints.
Evidence of true conversion is seen in sanctification, as one is being conformed to the image of Christ, note Romans 8:26-30. This transformation happens to all in Christ, not just some; 2 Corinthians 3:18ff.
Evidence of conversion is a necessity, if there is no evidence, there was no conversion.
Let me put it to you like this: In salvation (justification) it is all of God, 100% him. It is therefore monergistic, it was accomplished by a single person namely the work of God. Man gets no glory here for anything.
God chose to save whom he willed according to his purpose; Ephesians 1 and did this all himself. Note 1 Corinthians 1:26-31 showing it is all because of him, not us.
After this comes the post conversion life, something we call sanctification. This is synergistic, meaning a cooperation of two, that is, cooperation of the converted and God which is caused by God’s working within them. Therefore God also gets all the glory here as well. Note Ezekiel 36:27, Philippians 2:12-13.
So, saying we are holding out faith is true yet most fail to recognize that is all to his glory as he causes it to take place. On the other hand those dismissing this as works salvation are making a category error as this isn’t about saving ones self, it is about post conversion sanctification.
The other side errs in thinking it is solely something they are doing, like they are keeping on believing &c. The only reason they do this is because God causes them to will and do it because they are truly converted. It adds nor contributes nothing to their justification or final redemption, it only evidences that God is doing this in them, causing their cooperation.