What is incumbent upon me if I wish to stop performing the two rak'ahs of gratitude and the two rak'ahs of seeking forgiveness that I vowed to perform daily, knowing that I only have my weekly allowance which I use to meet my needs, and that saving enough to feed the needy as expiation would deprive me of my needs and require a long time? Is it permissible for me to fast for three days instead of feeding the needy?

If the questioner has vowed to perform two rak'ahs of prayer daily as an act of gratitude to Allah, she must fulfill this vow. It is not permissible for her to stop performing it except with a valid excuse. If she leaves it without an excuse, she must make up for it, and she incurs sin for abandoning them. If she becomes unable to perform them due to an inability that is not expected to cease, then she must offer an expiation for breaking an oath (feeding ten poor persons, or clothing them, or freeing a slave; and if she cannot find these, then fasting for three days). It is advised not to resort to such vows.