The Shofar in the Bible
The following is a partial list of (over 80) places where the Shofar is mentioned in the Bible. Depending on the translation you are using, the Shofar may be referred to as horn or trumpet. In the Hebrew original it is always Shofar.
Shofar sounded by God at the giving of the Torah on Mount Sinai.
Exodus 16:19 And it came to pass on the third day, when it was morning, that there were thunders and lightnings and a thick cloud upon the mount, and the voice of a horn exceeding loud; and all the people that were in the camp trembled.
Exodus 19:19 And when the voice of the horn waxed louder and louder, Moses spoke, and G-d answered him by a voice.
God Commands the Shofar to be Blown on the New Year (Rosh Hashana)
Leviticus 23:24 Speak unto the children of Israel, saying: In the seventh month, in the first day of the month, shall be a solemn rest unto you, a memorial proclaimed with the blast of horns, a holy convocation.
Leviticus 25:9 Then shalt thou make proclamation with the blast of the horn on the tenth day of the seventh month; in the day of atonement shall ye make proclamation with the horn throughout all your land.
The Capture of Jericho from the Book of Joshua
1 Now Jericho was straitly shut up because of the children of Israel: none went out, and none came in. 2 And the Lord said unto Joshua: 'See, I have given into thy hand Jericho, and the king thereof, even the mighty men of valour. 3 And ye shall compass the city, all the men of war, going about the city once. Thus shalt thou do six days. 4 And seven priests shall bear seven rams' horns before the ark; and the seventh day ye shall compass the city seven times, and the priests shall blow with the horns. 5 And it shall be, that when they make a long blast with the ram's horn, and when ye hear the sound of the horn, all the people shall shout with a great shout; and the wall of the city shall fall down flat, and the people shall go up every man straight before him.' 6 And Joshua the son of Nun called the priests, and said unto them: 'Take up the ark of the covenant, and let seven priests bear seven rams' horns before the ark of the Lord.' 7 And he said unto the people: 'Pass on, and compass the city, and let the armed body pass on before the ark of the Lord.' 8 And it was so, that when Joshua had spoken unto the people, the seven priests bearing the seven rams' horns before the Lord passed on, and blew with the horns; and the ark of the covenant of the Lord followed them. 9 And the armed men went before the priests that blew the horns, and the rearward went after the ark, the priests blowing with the horns continually. 10 And Joshua commanded the people, saying: 'Ye shall not shout, nor let your voice be heard, neither shall any word proceed out of your mouth, until the day I bid you shout; then shall ye shout.' 11 So he caused the ark of the Lord to compass the city, going about it once; and they came into the camp, and lodged in the camp. 12 And Joshua rose early in the morning, and the priests took up the ark of the Lord. 13 And the seven priests bearing the seven rams' horns before the ark of the Lord went on continually, and blew with the horns; and the armed men went before them; and the rearward came after the ark of the Lord, the priests blowing with the horns continually. 14 And the second day they compassed the city once, and returned into the camp; so they did six days. 15 And it came to pass on the seventh day, that they rose early at the dawning of the day, and compassed the city after the same manner seven times; only on that day they compassed the city seven times. 16 And it came to pass at the seventh time, when the priests blew with the horns, that Joshua said unto the people: 'Shout; for the Lord hath given you the city. 17 And the city shall be devoted, even it and all that is therein, to the Lord; only Rahab the harlot shall live, she and all that are with her in the house, because she hid the messengers that we sent. 18 And ye, in any wise keep yourselves from the devoted thing, lest ye make yourselves accursed by taking of the devoted thing, so should ye make the camp of Israel accursed, and trouble it. 19 But all the silver, and gold, and vessels of brass and iron, are holy unto the Lord; they shall come into the treasury of the Lord. 20 So the people shouted, and the priests blew with the horns. And it came to pass, when the people heard the sound of the horn, that the people shouted with a great shout, and the wall fell down flat, so that the people went up into the city, every man straight before him, and they took the city. 21 And they utterly destroyed all that was in the city, both man and woman, both young and old, and ox, and sheep, and ass, with the edge of the sword.
Gideon uses Shofar to Attain Victory. From Judges chapter 7
16 And he divided the three hundred men into three companies, and he put into the hands of all of them horns, and empty pitchers, with torches within the pitchers. 17 And he said unto them: 'Look on me, and do likewise; and, behold, when I come to the outermost part of the camp, it shall be that, as I do, so shall ye do. 18 When I blow the horn, I and all that are with me, then blow ye the horns also on every side of all the camp, and say: For HaShem and for Gideon!' 19 So Gideon, and the hundred men that were with him, came unto the outermost part of the camp in the beginning of the middle watch, when they had but newly set the watch; and they blew the horns, and broke in pieces the pitchers that were in their hands. 20 And the three companies blew the horns, and broke the pitchers, and held the torches in their left hands, and the horns in their right hands wherewith to blow; and they cried: 'The sword for HaShem and for Gideon!' 21 And they stood every man in his place round about the camp; and all the host ran; and they shouted, and fled. 22 And they blew the three hundred horns, and HaShem set every man's sword a against his fellow, even throughout all the host; and the host fled as far as Beth-shittah toward Zererah, as far as the border of Abel-meholah, by Tabbath.
The Return of the Ark of the Lord.
2 Samuel 6:15 So David and all the house of Israel brought up the ark of the LORD with shouting, and with the sound of the horn.
The Annointing of King Solomon. From 1 Kings Chapter 1
34 And let Zadok the priest and Nathan the prophet anoint him there king over Israel; and blow ye with the horn, and say: Long live king Solomon...39 And Zadok the priest took the horn of oil out of the Tent, and anointed Solomon. And they blew the ram's horn; and all the people said: 'Long live king Solomon.'
When the Messiah comes, God will blow a Shofar to gather in the exiles.
Isaiah 27:13 And it shall come to pass in that day, that a great horn shall be blown; and they shall come that were lost in the land of Assyria, and they that were dispersed in the land of Egypt; and they shall worship the LORD in the holy mountain at Jerusalem.
Used to Praise God
Psalms 150:3 Praise Him with the blast of the horn; praise Him with the psaltery and harp.