Testimonies are great things about what the Lord has done for us, but no-one will be offended when you talk about what God has done for you. You need to be specific about sin, about Christ's death on the cross, about others' need for a saviour, and about their need to repent and trust in Christ.
Mark DeverWe may be sinking in the North Atlantic in the most famous ship disaster of all time, but God can still use us to reach out and save others through our witness.
Mark DeverWe need to be realistic and recognize that there will be times when we won't be sharing our faith out of an overwhelming sense of joy. When that happens, that's a call to look at our own devotional lives. Are we putting our hearts and minds before the Lord and under his cross everyday? Do we remind ourselves continually that we have been ransomed by the death of the Saviour? When we meditate on Christ's death for us, it doesn't mean that we never have struggles in our obedience, but it does help.
Mark DeverPride causes us to care more about what our non-Christian friends think of us than what God will do to them in their sin.
Mark Dever