This is a Bible teaching on 2 Timothy 1:13-14. It details the importance of continually guarding the deposit of the Gospel that was entrusted to us by the power of the Holy Spirit in us.

The word guard as it is found in Helps Word Studies is as follows,

Pronounced (foo-las-so)
5442 phylássō (akin to 5441 /phýlaks, "a military guard") – properly, preserve by "having an eye on" (J. Thayer), referring to the uninterrupted vigilance shepherds show in keeping their flocks (see Lk 2:8, used with 5438 /phylakḗ, "a military guard," i.e. exercising unbroken vigilance as a military guard).

5442 /phylássō ("keep watch over, keep secure") emphasizes the needed vigilance to keep what is entrusted. Thus 5442 (phylássō) is often used in the NT in the Greek middle voice meaning, "Personally be on guard against," stressing the constant, personal interest involved with the guarding.

Guard, Helps Word Studies (2020) taken from

https://biblehub.com/greek/5442.htm

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