Guidance

Guidance, also known as divine fortune, was a cantrip, or a channel divinity prayer cast by all clerics. When the prayer version of divine fortune was cast, the cleric using it became, for a moment, more resistant to ill effects while simultaneously gaining additional combat proficiency. After the effects had worn off, divine fortune could not be recast, nor could any other channel divinity prayer be cast, until the cleric rested for at least a few minutes, in order to regain the concentration needed for the casting. The post-spellplague cantrip version had no such limitation.

History
Prior to the Spellplague and after the Second Sundering, divine fortune was more commonly known as guidance and was slightly less powerful, being considered an orison. It could also only be cast a number of times per day equal to the number of times a cleric had prepared for its usage. There was also a similar evocation used by druids.

Intervention
When people donated money to a church of deity and did something that had to do with that particular deity's portfolio, there was a chance, increasingly higher with increasing donation, that they benefited from a spontaneous guidance spell. Resistance and virtue were also one of those.