Deuteronomy 15:21
And if there be any blemish therein, as if it be lame, or blind, or have any ill blemish, thou shalt not sacrifice it unto the LORD thy God. And if there be any blemish therein, as if it be lame, or blind, or have any ill blemish, thou shalt not sacrifice it unto the LORD thy God.
No animal with any defect was to be presented to the Lord as a sacrifice, whether lameness or blindness or any other ill blemish. What was acceptable had to be without blemish, chosen from the best of the flock or field, not from what was weak or defective. It was also to be given freely, not grudgingly nor in a stinted way prompted by covetousness.
When applied to providing a house of worship, a grudging or inferior contribution is such a lame offering, so worshipers are to give their best and with care and generosity prepare a suitable and comfortable place for worship. A freewill offering is required in order for blessing to rest upon a family and its possessions, while withholding a suitable share brings curses upon harvests and flocks and may bring affliction upon the family itself.