Page 85 of the Big Book talks about serving God. My experience of serving God is that it is motivated only by a desire to serve God. That motivation is not subject to outside influence. The reason this produces more consistent action in me than self-serving is that self-serving is all about a transaction: taking action to get something back. If I cease valuing what I get back, or I do not get back what I anticipated, the motivation falters. Self-serving is about conditional giving; God-serving is about unconditional giving.