In the first reading, Habakkuk wonders how long he must wait for the Lord to answer. He sees unjust people exploiting the poor and getting away with murder. He laments: "Why doesn't God act? What's taking God so long?" (see Hab 1:13)
In the Gospel reading, Jesus also asks: "How long?" He's wondering how long He must wait for us to answer. Jesus cries: "How long must I remain with you? How long must I endure you?" (Mt 17:17)
If we think things are taking a long time, imagine how God must feel! He's been waiting for us to bring the gospel message to the ends of the earth (Acts 1:8). It's been two thousand years and over half the world's people still do not believe in God, much less believe in Jesus. God must be wondering: "How long, O My people?"
Jesus is waiting for us to work with Him in establishing His kingdom (see Heb 10:13). In the United States, we've been going backwards in the last forty years, not forward. Jesus must be wondering: "How long, O My people?"
"The Lord does not delay" (2 Pt 3:9), but we, His people, are masters of delay. We have all kinds of excuses for not carrying out His wishes (see Lk 14:18-20). We have wasted enough time (1 Pt 4:3). Let's spend the rest of our life living for the kingdom of God (1 Pt 4:2).