I believe, Dr. A. B. Simpson, founder of The Christian and Missionary Alliance was the originator of the Faith Promise methodology (note that definitions vary). AB suggested three steps in faithful giving: ability, sacrifice, and faith. That is to: (1) determine what you can give for missions, (2) add some by sacrifice, and (3) then add some by faith in God's additional provision. Uhmmm …
Many use 2 Corinthians 8:2-3 and 9:6-15 as a defense of these "pledges" [which is actually called a "commitment" between you and God. Some tend to go overboard in saying it is not a pledge, though one of the definitions of a "pledge" is: "to pay (an amount of money) as a contribution to a charity or service, especially at regular intervals"]. Nonetheless, I do not see any CLEAR teaching of pledges in 2 Cor. 8-9 - the people's crops and flocks could vary, a "specific amount" for the total offering had not yet been decided upon by all (2 Cor. 9:6), just that they were willing and excited about giving, (2 Cor. 8:11; 9:2), et. al. It also seems to be a kind of a self-COMPULSION (2 Cor. 9:7) once it is entered into. What if there is sickness in the family (1 Tim. 5:8, etc.) and the funds are needed for a family members very life? You can get yourself into a spiritual dilemma that one way or the other will lead to sin! James 5:12 says, "But above all things, my brethren, swear not, neither by heaven, neither by the earth, neither by any other oath: but let your yea be yea; and your nay, nay; lest ye fall into condemnation" (e.g. Matt. 5:34-37; 12:36-37; Ex. 20:7; Deut. 5:11). Thus, if you do "commit to it," you had "better do it," but then you have "self-compulsion." On the other hand, planned giving "during normal life" allows one to produce a more feasible budget for living by cheerful faith. The church may also plan more effectively using this type of giving methodology.
So, in conclusion I plan (2 Cor. 8:5, 10) my "faith promise" on the condition of "if the Lord will, we shall live, and do this, or that" (Jam. 4:15) with cheerfulness, faith, and obediently (2 Cor. 9). My budget is planned accordingly and my church/missions may depend on it to the extent the Lord provides (2 Cor. 9:10-11; Luke 11:41; 1 Cor. 16:2). However, should serious circumstances come about where these funds are needed elsewhere - which would violate scripture if not done - then I am not under any obligation (compulsion - my church may even need to assist me) to give ….., but I still can "even beyond [my] ability" (2 Cor. 8:3), if I do not violate other commands of scripture….
