'Mastery' isn't a single destination or an arrival point - it's a lifestyle. A mindset. An approach.

When it comes the Lord and His teachings, nothing is ever a 'singular' lesson, unrelated to His Word on whole. As He tells us in Isaiah, it is, "Precept upon precept, line upon line, here a little, there a little" - and this is the case whether you are just learning something for the first time, or learning it on an infinitely deeper level than you would've thought possible.

Verses:

Isaiah 28:10, 13

Luke 10:25-37, Parable of the Good Samaritan

Joshua 1:8 & Psalm 1:2, meditate on the word day and night

James 1:22-25, 'doers' of the word

Romans 10, not earning righteousness, but living from it