St. Paul made it very clear in many passages that we were to imitate and emulate him, as an example, as he in turn imitated Christ (also that we should imitate God, other holy persons, and be an example, ourselves, to others). This provides a strong biblical rationale for the veneration (strong honoring; not worship!) of saints:
Romans 4:12 (RSV) . . . follow the example of the faith which our father Abraham had before he was circumcised.
1 Corinthians 4:16 I urge you, then, be imitators of me.
1 Corinthians 11:1 Be imitators of me, as I am of Christ.
Ephesians 5:1 Therefore be imitators of God, as beloved children.
Philippians 3:17 Brethren, join in imitating me, and mark those who so live as you have an example in us.
Philippians 4:9 What you have learned and received and heard and seen in me, do; and the God of peace will be with you.
1 Thessalonians 1:6-7 And you became imitators of us and of the Lord, for you received the word in much affliction, with joy inspired by the Holy Spirit;  so that you became an example to all the believers in Macedo’nia and in Acha’ia.
1 Thessalonians 2:14 For you, brethren, became imitators of the churches of God in Christ Jesus which are in Judea; for you suffered the same things from your own countrymen as they did from the Jews,
1 Thessalonians 4:1 Finally, brethren, we beseech and exhort you in the Lord Jesus, that as you learned from us how you ought to live and to please God, just as you are doing, you do so more and more.
2 Thessalonians 3:7-9 For you yourselves know how you ought to imitate us; we were not idle when we were with you,  we did not eat any one’s bread without paying, but with toil and labor we worked night and day, that we might not burden any of you.  It was not because we have not that right, but to give you in our conduct an example to imitate.
1 Timothy 1:16 but I received mercy for this reason, that in me, as the foremost, Jesus Christ might display his perfect patience for an example to those who were to believe in him for eternal life.
1 Timothy 4:12 set the believers an example in speech and conduct, in love, in faith, in purity.
2 Timothy 1:13 Follow the pattern of the sound words which you have heard from me, in the faith and love which are in Christ Jesus;
John 13:15 For I have given you an example, that you also should do as I have done to you.
Hebrews 6:12 so that you may not be sluggish, but imitators of those who through faith and patience inherit the promises.
Hebrews 13:7 Remember your leaders, those who spoke to you the word of God; consider the outcome of their life, and imitate their faith.
James 5:10 As an example of suffering and patience, brethren, take the prophets who spoke in the name of the Lord.
1 Peter 2:21 . . . Christ also suffered for you, leaving you an example, that you should follow in his steps.
1 Peter 5:3 not as domineering over those in your charge but being examples to the flock.
3 John 1:11 Beloved, do not imitate evil but imitate good. He who does good is of God; he who does evil has not seen God.
Photo credit: The Preaching of St. Paul at Ephesus (1649), by Eustache Le Sueur (1616-1655) [public domain / Wikimedia Commons]
Summary: St. Paul taught us to imitate him, as he in turn imitated Christ. These & similar passages provide a biblical rationale for the veneration & honor (not worship!) of saints.