Preaching focuses on a call to action more so than explaining something. Teaching focuses on explaining something more so than a call to action. For example John the Baptist in Matthew 3:2 and Jesus in Matthew 4:17 preached saying repent ye for the kingdom of heaven is at hand. Scriptures that support preaching focus on a call to action include Matt 3:1-2; 4:17; Rom 10:8-10, 11-14, 15-17; Judges 4:4-5,6-7,8-10.
There are many ways to describe the similarity and difference between preaching and teaching. Non-believers require more preaching than teaching. Believers may require more teaching than preaching. Yet, both groups require some measure of both preaching and teaching at least at some points in time. One might say preaching is designed to move a person to some end; teaching is designed to tell a person in some detail how to move.
A herald is one that goes before or announces the coming of another or news about another proclaiming or otherwise conveying authorized news. As such a herald is an official messenger authorized by the one he or she represents. A herald actively promotes or advocates for another or something. An ambassador is a herald who is an official messenger of the one the ambassador represents. The scripture teaches all Christians, male and females, are ambassadors for Christ ( 2 Cor 5:20) and are therefore heralds of the Gospel (Good News) of Jesus Christ. Preachers are heralds concerning Jesus Christ. So then males and females may be preachers in the sense of ambassadorship so long as the distinction in the biblical role of male and female is maintained.
One ordinarily consider preaching as occurring publicly. However, the account of the prophet Nathan speaking to David (2 Samuel 12:7) and the account of the prophetess Huldah speaking to the men as requested by the King (2 Kings 22:14-20) shows preaching may occur privately. Indeed both Nathan and Huldah were heralds, ambassadors, official messengers from God.
Prophesizing is a special kind of preaching involving foretelling and/or forthtelling. Prophecy is delivering a message received directly from God; prophesizing is not simply setting forth of truths already established in the Bible less every Bible Student, every Sunday School Student would prophesy on a regular basis. But the Bible clearly establishes that certain men and certain women are called to prophesy but not all men and not all women are so called. This is evident in some men being called prophets and certain women being called prophetess and mentioning of females who prophesy in Acts 21:9 and 1 Corinthians 11:5.
The Bible provides a definition of prophecy when you combine Exodus 4:10-16, Exodus 7:1-2, and 2 Peter 1:20-21. These scriptures show that prophecy is divine spontaneous utterance, oral or written, setting forth a revelation from God that is previously unknown or at least not widely known; here spontaneous means it is void of any stimuli other than God’s Holy Spirit. These scripture show that prophecy is not repeating that which one has learned from study or heard someone else say God has said, again less we all prophesy on a regular basis. Peter shows that prophecy is not about interpretation of scripture by humans nor is it about the will of humans. Peter shows that prophecy is about the Holy Spirit moving upon men and women to utter divine revelatory speech.
Foretelling talks about the future. Forthtelling involves talk about the now and possibly the past but both are not at least not primarily about things already revealed in scripture. Deborah foretold regularly in giving an inspired revelation or answer or judgment to a problem or question or conflict or contention. Yet, this was not in a worship assembly. Thus, prophecy is not about preaching from the biblical text.
In 1 Corinthians 14:3 Paul speaks of at least some prophecy involving edification, exhortation, and comfort. Yet, he never says that all edification, exhortation, and comfort is prophecy. So preaching from the biblical text to edify, exhort, and comfort is not prophecy as referred to in 1 Corinthian 14:3. In fact in 2 Timothy 4:2 Paul tells Timothy to “Preach the word; be instant in season, out of season; reprove, rebuke, exhort with all longsuffering and doctrine.” We see here he uses the word exhort. We also know that the Old Testament prophets rebuked and reproved the people. So clearly both prophecy and ordinary preaching can involve a variety of elements.
In 1 Corinthians 14:6 Paul says “Now, brethren, if I come unto you speaking with tongues, what shall I profit you, except I shall speak to you either by revelation, or by knowledge, or by prophesying, or by doctrine?” So we see that at least in some contexts word of knowledge and revelation and doctrine may differ from prophecy.
The bottom line is that prophecy is foretelling and forthtelling involving words received directly from God and are not regular occurrences but rarities. Thus prophecy is not ordinary preaching of the biblical text nor is ordinary well known biblical truths or application of those truths to everyday life no matter how ingeniously one frames those truths.
To God Be the Glory!