en_tn_condensed/act/20/28.md

Paul continues to speak.

and about all the flock ... and not spare the flock.

This is an extended metaphor. The leaders of the church are supposed to care for the people under them and protect them from enemies just as a shepherd would care for his flock of sheep and protect them from wolves. (See: rc://en/ta/man/translate/figs-metaphor)

the assembly of the Lord which he purchased with his own blood

"The people Christ bought by shedding his blood on the cross" (See: rc://en/ta/man/translate/figs-metaphor)

draw away the disciples after them

"Convince people who are followers of Christ to follow their own, false, teaching"