Hebrews 12:1-2 – Therefore, since we are surrounded by so great a cloud of witnesses, let us also lay aside every weight, and sin which clings so closely, and let us run with endurance the race that is set before us, looking to Jesus, the founder and perfecter of our faith, who for the joy that was set before him endured the cross, despising the shame, and is seated at the right hand of the throne of God.
There are hints here about how to run this race properly, effectively, efficiently
1 – Listen to those who have done it before – “… since we are surrounded by so great a cloud of witnesses. This gives us a picture of the OT saints watching us and cheering us on as we run our race. That may be part of what is being said but it is not the main thing. There is no evidence anywhere in the Scriptures that saints who have died are able to watch us. We may speak about “mom looking down on us” but that is a fiction. In a prayer meeting in Grand Manan one evening a lady asked me if people in heaven could see us. Before I could answer another lady yelled out “It wouldn’t be heaven if they could”. One of the best theological statements I have ever heard. Another lady at another time told me she was terrified that now that her mother was in glory she would be able to see what she was up to. In any case, this verse is not talking primarily about saints of the past looking down on us and cheering us on. Witnesses are not just people who watch. They are people who testify to what they have seen heard or experienced. And that is what the OT believers do for us. They tell us, through the biblical accounts of their lives, what God was able to do through them as they trusted Him.
Hebrews 11 is about the OT believers who had great faith despite the fact that they had not received the promise that we have received – Jesus Christ. They believed God and did the great things they did because they believed that God cannot lie and that whether they lived to see the Messiah or not, God was going to send Him and it was worth all that they would suffer. These OT believers are witnessing to us that it is possible to live in obedience and faith. They did all the great things that they did without even having the promise of the Messiah realized in their lifetimes. They fixed their sights on a Messiah who was yet to come and God empowered them through that to endure in their race.

32 And what more shall I say? For time would fail me to tell of Gideon, Barak, Samson, Jephthah, of David and Samuel and the prophets— 33 who through faith conquered kingdoms, enforced justice, obtained promises, stopped the mouths of lions, 34 quenched the power of fire, escaped the edge of the sword, were made strong out of weakness, became mighty in war, put foreign armies to flight. 35 Women received back their dead by resurrection. Some were tortured, refusing to accept release, so that they might rise again to a better life. 36 Others suffered mocking and flogging, and even chains and imprisonment. 37 They were stoned, they were sawn in two, they were killed with the sword. They went about in skins of sheep and goats, destitute, afflicted, mistreated— 38 of whom the world was not worthy—wandering about in deserts and mountains, and in dens and caves of the earth.39 And all these, though commended through their faith, did not receive what was promised, 40 since God had provided something better for us, that apart from us they should not be made perfect.

Brothers and sisters in Christ – we have received the Messiah. We know how the Old  and New Testaments work together. We have the outpouring of the Holy Spirit. We have the church. We have the teachings of Jesus and the Apostles. We have the promise of the second coming. We have much more than the OT saints had. If they could live by faith how much more should we be able to? They testify to us that disobedience and sin and failure and immorality are not inevitable. It is possible to obey and live victoriously. We have all we need in order to do so. We like to grumble about various things in our lives that excuse us from living the life that we are called to live, but they are slim excuses at best and in reality are simply unbelief. We want and expect to get to heaven to be with Jesus for eternity without having suffered here for Him – and that is a lie. What they set their sights on as a promise yet to be realized, we look back on as a promise fulfilled – Jesus Christ dying and rising from the dead for us. We are surrounded by a great cloud of testimony – so – let us run the race – with perseverance – fixing our eyes on Jesus – who designed and authored our faith.