Concerning Christian giving, the word of God is clear:

"For if there is first a willing mind, it is accepted according to what one has, and not according to what he does not have." (2 Cor. 8:12)

Therefore, your liberality starts with YOU having a willing mind. Ministers should only give you sound teaching on giving, inform you of the needs and encourage you.

Once you are willing, promptly decide on what to give and set it aside (physically or in your mind) - and do it without delay or fanfare.

Let no one coerce you into giving what you do not have. What you have is what is expected by God and accepted by Him - not what you don't have. Don't fall for sweet words or threats of evil prophecies. And overcome your own covetousness leading to gullibility.

However, note that all this is without prejudice to the issue of sacrificial giving in which you actually have, but it seems too costly or inconvenient for you to give. Such situations are challenges Christians should overcome. It is called "giving beyond ability" and God appreciates it, provided it is done freely and with a willing heart.