I would love to hear your grandparents’ pastor give the biblical basis for denying admittance to the church for those who haven’t paid. This seems to me a direct contradiction of 2 Cor 9:7 that commands that we are not to give out of compulsion.
My church takes a different approach. The church encourages members (they specifically tell visitors that they are not expected to give anything) to agree to give at least 10% for 90 days. If after that 90 days, a person feels that the giving created a financial hardship or that they did not receive a blessing from God as He promised He would give in Malachi 3:10, then they will give all the money back, no questions asked. They also make clear that if people think it is a trick to get them to give, then they are free to give to another ministry or local church in the area instead. The point of giving is not that God needs our money, but that we need to avoid materialism. You cannot serve God and money.
The tithe was a matter of law, and many people therefore believe that since Jesus fulfilled the law, we are not obligated to tithe. I happen to be one of them. If that is true, however, what are we obligated to do? As always seems to be the case, I think Jesus raised the bar.
2 Corinthians 8
9 For you know the grace of our Lord Jesus Christ: although He was rich, for your sake He became poor, so that by His poverty you might become rich.
Matthew 5
40 As for the one who wants to sue you and take away your shirt, let him have your coat as well. 41 And if anyone forces you to go one mile, go with him two. 42 Give to the one who asks you, and don’t turn away from the one who wants to borrow from you.
Luke 3
10 “What then should we do?” the crowds were asking him. 11 He replied to them, “The one who has two shirts must share with someone who has none, and the one who has food must do the same.”
Matthew 19
21 “If you want to be perfect,” Jesus said to him, “go, sell your belongings and give to the poor, and you will have treasure in heaven. Then come, follow Me.” 22 When the young man heard that command, he went away grieving, because he had many possessions.
I personally believe that we are to give out of love, not just a set amount.
Luke 11
42 "But woe to you Pharisees! You give a tenth of mint, rue, and every kind of herb, and you bypass justice and love for God. These things you should have done without neglecting the others.
1 Corinthians 13
3 And if I donate all my goods to feed the poor, and if I give my body to be burned, but do not have love, I gain nothing.
In return, God gives to us by the standard that we choose to give. I think that what God gives is not necessarily material, but spirtual, as well.
Luke 6:38
Give, and it will be given to you; a good measure, pressed down, shaken together, and running over will be poured into your lap. For with the measure that you use, it will be measured back to you."
2 Corinthians 9
6 Remember this: the person who sows sparingly will also reap sparingly, and the person who sows generously will also reap generously.
Televangelists who beg for money are charlatains. I prefer the approach Paul took:
Acts 20
33 I have not coveted anyone’s silver or gold or clothing. 34 You yourselves know that these hands have provided for my needs, and for those who were with me. 35 In every way I’ve shown you that by laboring like this, it is necessary to help the weak and to keep in mind the words of the Lord Jesus, for He said, ‘It is more blessed to give than to receive.’ "
My bottom line thoughts on giving are that we are required to give out of love (which will invariably be more extravagant than what the law required) and that the amount will always be such that it breaks the hold of materialism in our lives. For some that amount will be more than others.