struggle to go in through the narrow door, because many I tell you seek to enter and are not able (Luke 13:24)
That we have to ask, seek, and knock to find our way seems a bit extraordinary. And that we can't really find something valuable that we can not physically see seems a contradiction. If not but that faith exists evidence and substance of things not seen. And that the Spirit guides us into the truth and the way also interceding for us when we do not know what to pray.
Maybe the reason we have to struggle to find the way is that if it were all given to us we would not find it valuable. How easily the fleshly child of God lost sight of what was valuable. God would bless them with earthly goods and they would find earthly things more valuable and turn their hearts from him.
Indeed we will struggle and endurance is needed to keep on the way. James writes the trial comes to teach us endurance and the intended purpose of endurance is to mature us. Mature us into the likeness of the image of Christ, Paul writes in Ephesians 4. And Peter tells us that the trial is a trial by fire, more precious than gold and silver in the eyes of God. Though it might not seem it at the time it is for our good and glory. The very definition Webster's dictionary gives of struggle is "to proceed with difficulty or with great effort." Struggling is to strive or contend to attain something in the face of difficulty or resistance.
... strengthing the souls of the disciples encouraging them to endure in faith and saying through many tribulations we must enter the kingdom of God (Acts 14:22)
This is what the apostles did in the early church, they encouraged others to endure in faith, to struggle and contend in the way. Tribulations come and we know their purpose but still, it is a struggle, and the very nature of struggling makes us weary. I visited a church and the pastor while talking about his trip to the "holy land" looked at a man who was clearly struggling and needed encouragement in the faith and said, "if you don't have joy you don't have Jesus."
Through many tribulations, we must enter the kingdom of God. You hear this said as an excuse often to avoid helping others who struggle, "Don't steal my joy." But in Christ true joy is not based upon earthly circumstances. And is often found in the struggle thus those who have found such treasure will not turn their heart from others who are struggling but will encourage them to contend. In fact, the scriptures tell us this might be the reason the trial comes so that we experience the struggle and can encourage others who are in the fire.
Paul experienced all kinds of hardships in this life. And he struggled with one thing in particular. Like a thorn in his side, it was always there bothering him, and it came through messengers of satan sent to torment him. He prayed for God to take it away but God said it was through weakness his power is perfected or matured in us. The degree and nature of the struggle will be various and some will struggle more than others, but all of God's children will and do struggle with something.
fight the good fight of faith, take hold of eternal life to which you were called, and confessed the good confession before many witnesses (1 Timothy 6:12)
Struggling is different than just bearing through a hard time, it is striving or contending to attain something. The word fight in this verse is the same word for struggle and contend ἀγωνίζομαι (agōnizomai) used in our feature verse "struggle to go in through the narrow door." So contend as a combatant, fight the good fight of faith to take hold of eternal life. Therefore the way to life is difficult so struggle, contend as a combatant, and fight to lay hold of that to which you have been called and have entered.