What is the ruling on preferring others in closeness, such as giving precedence to one's father or a scholar for the first row in prayer?

Preferring others in acts of proximity [to God] is of two types: First, obligatory acts of proximity. It is not permissible to prefer others in these, and an example of this is preferring someone else with the only water available for ablution. This is forbidden because it entails abandoning an obligation. Second, supererogatory acts of proximity. The general principle here is not to prefer others, unless there is a benefit that necessitates it, such as giving precedence to a father in a queue if he would be affected by not being given precedence. However, if he would not be affected, then it is better to remain in one's place.