Summary: Many professing Christians treat the Faith as though it were optional; God calls us to absolute commitment.
“We must pay much closer attention to what we have heard, lest we drift away from it. For since the message declared by angels proved to be reliable, and every transgression or disobedience received a just retribution, how shall we escape if we neglect such a great salvation? It was declared at first by the Lord, and it was attested to us by those who heard,” 
“How shall we escape if we neglect such a great salvation?” The Great Question posed in the message this day is frequently employed when confronting outsiders. However, the question was intended to confront those who appeared at one time to be walking in the Faith, but who have begun to turn aside. On one occasion, Jesus made a startling statement when He said, “Enter by the narrow gate. For the gate is wide and the way is easy that leads to destruction, and those who enter by it are many. For the gate is narrow and the way is hard that leads to life, and those who find it are few” [MATTHEW 7:13, 14]. The entrance to one gate is wide and easy, and the way beyond the gate is spacious; but it leads to destruction and ruin. The majority of mankind opts to follow that path and to pass through that particular gate. Another gate that Jesus described is said to be constricted; and after you have passed through that gate you will discover that the path leading beyond is narrow, requiring your full attention.
You know quite well the encouragement Paul and Barnabas offered to those who had come to faith during the first missionary tour. “When [the missionaries] had preached the gospel to that city and had made many disciples, they returned to Lystra and to Iconium and to Antioch, strengthening the souls of the disciples, encouraging them to continue in the faith, and saying that through many tribulations we must enter the kingdom of God” [ACTS 14:21, 22].
This same theme was presented at other times as the Master taught. Near the end of His ministry in Judea, facing the Passion that was about to break over Him, we see the Master presenting this same teaching. “[Jesus] went on his way through towns and villages, teaching and journeying toward Jerusalem. And someone said to him, ‘Lord, will those who are saved be few?’ And he said to them, ‘Strive to enter through the narrow door. For many, I tell you, will seek to enter and will not be able. When once the master of the house has risen and shut the door, and you begin to stand outside and to knock at the door, saying, “Lord, open to us,” then he will answer you, “I do not know where you come from.” Then you will begin to say, “We ate and drank in your presence, and you taught in our streets.” But he will say, “I tell you, I do not know where you come from. Depart from me, all you workers of evil!” In that place there will be weeping and gnashing of teeth, when you see Abraham and Isaac and Jacob and all the prophets in the kingdom of God but you yourselves cast out. And people will come from east and west, and from north and south, and recline at table in the kingdom of God. And behold, some are last who will be first, and some are first who will be last’” [LUKE 13:22-30].