I have found that Salvation was an intrusion into the life that I wanted to live. It is still an intrusion when my flesh wants to run things. But it is more and more a welcome intrusion.
For unbelievers whose hearts are not open, Christian witnesses will be unwelcome intruders to their hearts and lives. To them Jesus Himself is an unwelcome intruder. God*s truths and instructions will also be unwelcome intruders. I remember occasions before I surrendered my heart to the Lord when I became angry at those who witnessed to me. I was not aware that I was angry with the Saviour who loved me and with His blessed truths. I was a natural man.
1 Corinthians 2:14: But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned.
I was spiritually blind.
Luke 8:10: And he said, Unto you it is given to know the mysteries of the kingdom of God: but to others in parables; that seeing they might not see, and hearing they might not understand.
In witnessing we should not be hurt, surprised or angry when people reject us, the Saviour and truth all at the same time. Sometimes they will accept us UNTIL we speak God*s Word or about Him. Sometimes they will continue to accept us and the Saviour and His Word. That is a clue that their heart may be open.
1 Samuel 8:7: And the LORD said unto Samuel, Hearken unto the voice of the people in all that they say unto thee: for they have not rejected thee, but they have rejected me, that I should not reign over them.
Other than trying to find out whether their hearts are open, there is no good reason to stop speaking God*s Word and speaking about Him and what He has done for you.
2 Timothy 4:2: Preach the word; be instant in season, out of season; reprove, rebuke, exhort with all longsuffering and doctrine.
We reinforce God*s truth if we are living the word as well as preaching it.
Acts 16:14: And a certain woman named Lydia, a seller of purple, of the city of Thyatira, which worshipped God, heard us: whose heart the Lord opened, that she attended unto the things which were spoken of Paul.
Since God is the one who opens hearts, it is vitally important that we pray for those that we witness to, before, during and after. Witnessing is like using the Word of God as a door-knocker. When we use the Word of God Jesus Himself will be the one knocking on their hearts* door. After some experience at witnessing we will be able to recognize closed doors and open ones. When we walk through the open ones we won*t be treated like intruders.
Revelation 3:20: Behold, I stand at the door, and knock: if any man hear my voice, and open the door, I will come in to him, and will sup with him, and he with me.
If they want the door shut, we ought not add force to it by slamming it shut from our side. If they seem to be trying to make us angry, it is as if they want us to help them slam the door. We should let them know in some way that if they change their mind or have questions in the future we would be willing to resume the conversation.
Then we should pray that we will not be the last witness that the Lord will provide for them and that He will open their hearts to His Son. I believe there have been occasions that I was the last one to witness to an individual. I have been troubled by that, especially when I remember that I did not pray for them after my failed witnessing.