Giving to the church should be a practice of believers only. The church does not need to accept the money of unbelievers. The Bible says that the Lord is not poor.
Finally, giving must be the practice of every believer - no matter what their financial situation. Everyone can give something.
[Deu 12:6 KJV] 6 And thither ye shall bring your burnt offerings, and your sacrifices, and your tithes, and heave offerings of your hand, and your vows, and your freewill offerings, and the firstlings of your herds and of your flocks:
Guidelines for Giving
Most of us, I daresay, associate the proverb "It is more blessed to give than to receive" with the offering on Sunday morning--even though for Paul () as well as for Jesus () it is a guiding principle for the Christian worker rather than the Christian giver. And while the principle is a helpful one when we consider the matter of financial contributions, questions of how much and to whom are still formidable ones for most Christians.
The Corinthians, to be sure, asked these same questions, and Paul responds with some practical guidelines for giving in 8:11-15. How helpful these guidelines are today will depend on how tied a church is to the legalistic practice of the "tithe." For it is curious that at no point here--or for that matter elsewhere in Paul's writings--is the tithe put forward as a guideline for giving. In fact, no New Testament writer either encourages "tithing" or presents it as the normative or even occasional practice of the church. Yet many of our churches assume that this is the accepted New Testament standard.
The standard proffered is, in reality, a higher one than the traditional tithe. In counseling the Corinthians on the question of how much, Paul says that they are to give, in the first place, according to [their] means (8:11). The text is literally "out of that which you have." The implication is clear. We are not called to give or to pledge what we do not have. Contributions are to be based on actual income, not hoped-for windfalls or even anticipated earnings.
Giving is also to be in proportion to our earnings (katho ean echh, v. 12). It is not a fixed percentage but relative proportion that is key. In fact, beyond the tithe of livestock and produce to support the Levites, the standard for Israel's giving was a proportional one. The person with many possessions is to make her gift of alms "proportionately," and the one with few possessions is to give "according to" the little he has (). A similar guideline is given in , where Paul instructs the Corinthians that they are to set aside a sum of money each week "in keeping with" their income (literally, "however one has prospered").
Proportional giving actually turns out to be a fairer standard than the traditional tithe. Whereas a fixed 10 percent would most likely be negligible for someone with an income of $100,000, it could well cripple a person with an income of $10,000. This is why Jesus had such high praise for the widow who contributed too small copper coins to the temple treasury. She gave that which provided for her daily necessities ("all she had to live on," ), while the rich contributed out of their surplus. And while both may have given 10 percent, proportionately the widow put in more than all the others combined (). This accords with Jesus' teaching elsewhere that we are responsible in direct proportion to how God has blessed us: "From everyone who has been given much, much will be demanded" ().
Second, needs are to be met out of a person's surplus, not necessary income (that which one needs for life's basic necessities; v. 14). The Macedonian churches, in giving out of their poverty, were the exception rather than the rule. The norm is the Corinthians' plenty supplying what the Judean churches need, so that in turn their plenty can supply what [the Corinthians] need (v. 14).
[ KJV] 6 But this [I say], He which soweth sparingly shall reap also sparingly; and he which soweth bountifully shall reap also bountifully. 7 Every man according as he purposeth in his heart, [so let him give]; not grudgingly, or of necessity: for God loveth a cheerful giver. 8 And God [is] able to make all grace abound toward you; that ye, always having all sufficiency in all [things], may abound to every good work: