Book of Hebrews
"Why lift up the hands which hang down, and the feeble knees;"
Verses one to thirteen of this chapter are chiefly concerned with hardship in the life of believer's, in addition to how having gone through these things there's a great reward in the here and now, that being holiness or what we today would call sanctification. Lewis in his short book “A Grief Observed” wrote regarding his late wife she was a sinful woman married to a sinful man, nowhere near a perfected saint, adding “the sword will be made even brighter.”
In a similar way, though clearly being concerned with this life, the author of Hebrews teaches that they lift hands which hang low, and feeble knees, “making straight paths for your feet, lest that which is lame be turned out of the way; but let it rather be healed.” (ver 13). Just looking back to Paul and his illustration of believers running for an imperishable crown seems so important here. We're running, but like if we literally run our body at some point just gives out, it fails and forces us to stop, no matter how badly we might want it to go on. Still in Hebrews we lift our knees up again, and we lift our hands again, because the word and spirit hasn't failed even if we do.
So the author is writing to believers, but he's afraid they may be turned out of the way, having their weak lame body parts drawn off of the path. Here we have a charge to stay in the way, to stick to the narrow path, not being drawn off as we're tempted to do by various things.
In verse one of the same chapter it's written ”let us lay aside every weight,” and let us lay aside the sins which beset us, this is any variety of sin. Some people's faith is shaken by their own intolerance, or education, or lust, wealth, some people can't imagine following a Jewish saviour because just to be a Jew earns their contempt. Whatever the reason the author is insisting in verses twelve and thirteen not to be drawn out of the way by these terrible things, however attractive they might appear to be.
In fact the importance of staying on this path (this path of holiness and faith shown perfect by our steadfastness in suffering) is stressed by what the early followers of Jesus were called. Christians were simply called followers of “the way.” For which I'm reminded of Christ teaching He is the way (Jn 14:6). These chapters and verses are often used in the famous Arminianism Vs Calvinism debate to try and prove that believers in Jesus can fall away, that they can be lost. Many people consider this book a strong fortress for Arminians, an Arminian “castle” is the term I've heard most often. Whether or not that's really the case is going to be explained in full as we explore the remainder of Hebrews.