“Behold, I have set before thee an open door, and no man can shut it: for thou hast a little strength, and hast kept my word.” – Revelation 3:8

“You have been faithful; therefore I will use you. You have been steadfast; therefore I will employ you.” For a considerable period of human life, it may be, God does not give to all of us a field of usefulness, but He provides a field of trial. There are some to whom He early opens the gate of usefulness, because He sees in them a spirit that will bear the temptation of success; but in many other cases it is questionable whether they could bear promotion, and therefore the Lord permits them to be tried in different ways until He sees that they are found faithful, and then He puts them into His service, and gives them an opportunity of bearing witness for Him…There are opportunities before you now which were not there before: these are placed before you especially because you have been tried, and have been proved faithful. If you will now begin to talk to others about that which you love so well, you will be astonished to find how gladly they will receive it from you. You have been a receiver yourself until now, and that is well and good; but, now that you have become filled, overflow to others, and let them receive of your joy.

Before you the Lord God has set an open door. Go ahead! Do not be afraid. People will be willing to hear what you have to say, and, what is more, people will be converted by what you say, for God has set before you this open door, and no man can shut it. It is amazingly easy to go through a door when it is wide open, and it will be very easy to you-much easier than you think, now that you have been schooled by God’s Spirit into steadfastness of character, just to say in God’s name, dependent upon God’s strength, what He has taught you. You will bring many to Christ, because you yourself abide in Christ. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/1814.cfm