Biblical Evidence for Veneration of Saints and Images
Where in the Bible do we find a physical object being venerated or shown honor, similar to an icon?
In one of my books (Revelation!: 1001 Bible Answers to Theological Questions), I used a Q&A format, where the answer to each question was a Bible passage. Here are the sections on veneration:
Veneration of Saints and Imitation of Holy Persons
Does St. Paul teach us to imitate him?
Philippians 4:8-9 (RSV) Finally, brethren, whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is gracious, if there is any excellence, if there is anything worthy of praise, think about these things.  What you have learned and received and heard and seen in me, do; and the God of peace will be with you.
Doesn't this detract from worship of God, by competing with it?
1 Corinthians 11:1 Be imitators [KJV, followers] of me, as I am of Christ.
So St. Paul sees no contradiction between imitating Him and imitating Jesus?
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.
Are we taught to venerate and imitate saints of the past?
Hebrews 6:12 so that you may not be sluggish, but imitators of those who through faith and patience inherit the promises.
Is there any example of honoring or venerating a person after his or her death?
2 Chronicles 32:33 And Hezeki'ah slept with his fathers, and they buried him in the ascent of the tombs of the sons of David; and all Judah and the inhabitants of Jerusalem did him honor at his death. And Manas'seh his son reigned in his stead.
Do we ever observe the permissible veneration of a living person?
1 Chronicles 29:20 Then David said to all the assembly, “Bless the LORD your God.” And all the assembly blessed the LORD, the God of their fathers, and bowed their heads, and worshiped [shachah] the LORD, and did obeisance [shachah] to the king. [KJV: “worshipped the LORD, and the king”]
Daniel 2:46-48 Then King Nebuchadnez'zar fell upon his face, and did homage to Daniel, and commanded that an offering and incense be offered up to him.  The king said to Daniel, “Truly, your God is God of gods and Lord of kings, and a revealer of mysteries, for you have been able to reveal this mystery.”  Then the king gave Daniel high honors and many great gifts,
Acts 16:29-31 And he called for lights and rushed in, and trembling with fear he fell down before Paul and Silas,  and brought them out and said, “Men, what must I do to be saved?”  And they said, “Believe in the Lord Jesus, and you will be saved, you and your household.”
Veneration of Angels and Men as God's Representatives
Do we ever see God allowing veneration and even bowing before a created angel?
Joshua 5:13-15 When Joshua was by Jericho, he lifted up his eyes and looked, and behold, a man stood before him with his drawn sword in his hand; and Joshua went to him and said to him, “Are you for us, or for our adversaries?”  And he said, “No; but as commander of the army of the LORD I have now come.” And Joshua fell on his face to the earth, and worshiped [shachah], and said to him, “What does my lord bid his servant?”  And the commander of the LORD's army said to Joshua, “Put off your shoes from your feet; for the place where you stand is holy.” And Joshua did so.
Is the “angel of the Lord” venerated?
Numbers 22:31 Then the LORD opened the eyes of Balaam, and he saw the angel of the LORD standing in the way, with his drawn sword in his hand; and he bowed his head, and fell on his face.
It’s always good to verify doctrine by the Bible, since it is God’s inspired revelation to mankind. We see that Catholic teaching is always in harmony with the Bible. But when we follow non-biblical traditions of men, we go astray.
Veneration of Images
Where do we find a physical object being venerated or shown honor, similar to an icon?
Joshua 7:6-7 Then Joshua rent his clothes, and fell to the earth upon his face before the ark of the LORD until the evening, he and the elders of Israel; and they put dust upon their heads.  And Joshua said, “Alas, O Lord GOD, why hast thou brought this people over the Jordan at all, to give us into the hands of the Amorites, to destroy us? Would that we had been content to dwell beyond the Jordan!
Did the temple have statues or carved images in it, associated with and always present during worship?
2 Chronicles 3:7 So he lined the house with gold -- its beams, its thresholds, its walls, and its doors; and he carved cherubim on the walls.
Did sacrifice and worship take place before the ark of the covenant?
1 Chronicles 16:1-4 And they brought the ark of God, and set it inside the tent which David had pitched for it; and they offered burnt offerings and peace offerings before God.  And when David had finished offering the burnt offerings and the peace offerings, he blessed the people in the name of the LORD,
 and distributed to all Israel, both men and women, to each a loaf of bread, a portion of meat, and a cake of raisins.  Moreover he appointed certain of the Levites as ministers before the ark of the LORD, . . .
Did the Jews worship God through the presence of the supernatural pillar of cloud?
Exodus 33:10 And when all the people saw the pillar of cloud standing at the door of the tent, all the people would rise up and worship, every man at his tent door.