Preaching the Gospel is not about how many scriptures you can quote; it’s about communicating those scriptures with, and by the Holy spirit. This is what we’re called to do as God’s children (beleivers) and ministers of the Gospel.
Anybody can sermonise or give great lectures and speeches, but without the Spirit, they’ll have no lasting impact.
Ephesians 5:18
AMP:And do not get drunk with wine, for that is debauchery; but ever be filled and stimulated with the [Holy] Spirit.
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This scripture passage is one of the reasons we are required to spend quality time fellowshipping the Spirit, praying in the Spirit, to be filled with the Spirit.
That way, our message and our preaching wouldn’t be persuasive words of man’s wisdom, but in the demonstration of the Spirit and of power.
We have been made able ministers of the new testament and not of the letter, but of the spirit, because the letter kills, but the spirit gives life
2 corinthians 3:5-6
5KJV:Not that we are sufficient of ourselves to think any thing as of ourselves; but our sufficiency is of God;
6KJV:Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life.
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We start to make spiritual progress when we understand that we really cannot do anything by our power or on our own. It is only by depending completely on the Spirit that we can minister in the Spirit.
We have been sent by the Spirit, and anointed of God. Therefore, we can only carry out His work by the power of the Spirit.