The Buddha was very fond of puns, double meanings, and wordplay. This Dhammapada explores the various meanings of "Yoga" as a work that results in an act of striving, striving which results in an act of application, and the contemplation which results from that striving - to understand the purpose of persistence (anuyunjati). The development of persistence IS the work of Yoga, which permits understanding.
The concept of persistence comes from the thought that there is no final or even subsequent sacrifice (ananuyaja). The persistence is involuntary, as no amount of choice can alter the reality that there is no final sacrifice or subsequent sacrifice. This type of understanding which arises from persistence, of understanding the limitations to choice, is better described as no longer deceiving, not lying, Ananuyoga (there are many kinds of understanding): A (not) - nanu (never) - yaj(a) (venerating) / yoga (yoking).
Hence, Anuyutta (applying oneself to, dealing with, practising, given to, intent upon) is also seen to mean an attendant, inferior or vassal - one who cannot choose but to engage in service. One who persists.