There is no exercising our calling without discipline. There is no bearing fruit without discipline.
Consider what the Bible says about the undisciplined life:
Through sloth the roof sinks in, and through indolence the house leaks. (Ecclesiastes 10:18)
The hand of the diligent will rule, while the lazy will be put to forced labor. (Proverbs 12:24)
The lazy person does not plow in season; harvest comes, and there is nothing to be found. (Proverbs 20:4)
I passed by the field of one who was lazy, by the vineyard of a stupid person; 31 and see, it was all overgrown with thorns; the ground was covered with nettles, and its stone wall was broken down. 32 Then I saw and considered it; I looked and received instruction. 33 A little sleep, a little slumber, a little folding of the hands to rest, 34 and poverty will come upon you like a robber, and want, like an armed warrior. (Proverbs 24:30-34)
In the Bible undisciplined and slothful ways are viewed as sinful.
Do you want to grow strong in Christ? Do you want to exercise your calling as a child of God with diligence and endurance? Do you want to flourish and bear fruit? Then take the advice of Psalm 1:
Delight in the word of God Meditate on God's word day and night You will be like a tree planted by streams of water! You will yield fruit when it is time!