Testimony is the written or spoken statement of someone. In Christian context, it is statement or account of what someone has encountered with God or what God has done for someone. A good example is the demoniac in the scripture below.
"The man from whom the demons had gone out begged to go with him, but Jesus sent him away, saying, “Return home and tell how much God has done for you.” So the man went away and told all over town how much Jesus had done for him." - Luke 8:28-29 NIV
Sometimes Jesus would tell somebody after healing or deliverance not to tell anybody, but on this occasion, He said go and tell thy people, what great things the Lord has done for you. Here it means go and advertise the Lord's work in your life. Telling what God has done for us is glorifying God. It is equally praising God. We praise God and make other people to praise God with us.
"And they overcame him by the blood of the Lamb, and by the word of their testimony; and they loved not their lives unto the death." - Revelation 12:11 JKV
To testify is to put a seal on the miracle God has done for us. When we are hiding it, it will be subject to the manipulation of the enemy. When it is testified, God completes it.
"As he was going into a village, ten men who had leprosy met him. They stood at a distance and called out in a loud voice, “Jesus, Master, have pity on us!” When he saw them, he said, “Go, show yourselves to the priests.” And as they went, they were cleansed. One of them, when he saw he was healed, came back, praising God in a loud voice. He threw himself at Jesus’ feet and thanked him and he was a Samaritan. Jesus asked, “Were not all ten cleansed? Where are the other nine? Has no one returned to give praise to God except this foreigner?” Then he said to him, “Rise and go; your faith has made you well.” - Luke 17:12-19 NIV
Scholars shows that the remaining nine died of leprosy. Only the Samaritan that returned was cured pamanently, a simple thank you means a lot. When ever someone render help to you learn to show appreciation that will enable him/she to do more for you. Testimony open doors for more. It is a show of gratitude to God. When we testify we are making God to do more for us.
