The scriptural basis for this concern is found in 2 Peter 1:10, and 2 Thess 2:11. Now, do not be deceived by those who say that I am claiming that tithing is essential to salvation. Not at all. Faith, which comes from hearing, is essential for salvation. But, deception from the devil, and delusion from God both could counterfeit such faith. Jesus gave many parables about people who thought when they died that they had faith for salvation. Only to find out too late that they were lost. The 2 Peter verse given above has for it's context the strongest emphasis of any command in scripture--"even more than" all diligence" is to be applied to the command, to make sure of your calling and election. God wants us to do this.
Delusion, according to the Thessalonians passage, is prevented by "receiving the love of the truth." Now, there are many commandments that pertain to truth. And, love is defined as keeping the commandments. The call is to make diligent provision for study of and keeping these commands, that tell us how to know what is true. One of those commands is to look at "signs." "Judging yourself."
In Malachi, we are told that we might receive from God the ability to discern the righteous from the wicked, Between one who serves God and one who does not serve Him (3:18) I have sought that gift, so that I might know who to warn of possibly being deluded. What I received was a warning that not giving at levels above the tithing levels was not an encouraging sign. And, ignoring such signs is itself a sign that one does not love the truth.
He said the remedy for delusion is to prepare your heart for a mentor, to "buy" instruction in wisdom, which is the fear of God. Get a mentor, and ask them to instruct you in how to know what is true, scriptural. Normally, we "buy" the truth by spending time, paying attention, and giving to the poor (not the mentor, unless they are poor, and have a need you can see.)
I post this here because I am not available to serve as such a mentor for anyone who is not a neighbor, who I do not know personally. If God wants me to help anyone this way, He will have to tell them without my being involved. My flesh is normally greedy, of course, among many other carnal inclinations. I do what God tells me to do to keep that flesh from getting its way in my life, or the life of others. In this case, I am so wealthy that I usually cannot think of anything I might do with more dollars, or whatever.