Is it permissible to practice ta'reedh (indirect communication/allusion) in concealing acts of worship for fear of ostentation (riyaa'), and is this better than open declaration, and does the ruling differ if one knows within oneself a desire for people to know of one's obedience?

Alluding in an answer is legally permissible and provides an alternative to lying, as mentioned by Al-Bukhari. Concealing acts of worship that the Shariah has not commanded to be openly displayed is preferable, especially when there is fear of showing off (riya'), due to the Almighty's saying: "Invoke your Lord with humility and in secret." Therefore, it is preferable for a Muslim to allude to conceal his good deed with a truthful statement from which something other than the reality is understood, and this is confirmed when there is a desire to show people his worship or a fear of showing off.