“The psalm (may have) originated in victory celebrations of Israel’s king and people (cf. II Chron. 20:27). Later it was probably used in periodic commemoration of God’s past goodness to the Davidic dynasty” Laymen, 684. “The ‘I’ standing collectively for Israel, verses 5-14, 17-19, 21, and 28 seem to portray a great deliverance which has come to a king, possibly David himself. There are similar sentiments in Psalm 18” Miller, 381. “It is best to see this as a corporate thanksgiving, although an individual leads in expressing gratitude on behalf of himself and the whole congregation” Longman, 399.  “The psalm uniquely combines corporate hymnic praise (vv. 1-4, 22-24, 29), individual thanksgiving (vv. 5-18, 21, 28); processional liturgy of entering the temple gates and processing to the altar (vv. 19-20, 26-27). It alternates between referring to Yahweh in the third person and addressing him in the second person” Broyles, 438. This was “perhaps as an entrance liturgy into the temple in Jerusalem, in much the same way that Psalms 15 and 24 may have been used” NICOT, 864. 

118:1-4 Give thanks to the LORD for His lovingkindness is good

118:1 Give thanks to the LORD, for He is good- I Chron. 16:34; II Chron. 5:13; 7:3; 20:21; Ps. 106:1; 107:1; 136:1; Jer. 33:11; Ezra 3:11

These same three groups, Israel, the house of Aaron, and those who fear the LORD, were mentioned in 115:9-13. See a similar list in 135:19-20 

118:5-9 The Speaker’s (the King’s) testimony of being rescued by God

118:10 All nations surrounded me- Verses 10-12 all begin with the same thought. The nations surround God’s people. The word surround is used 4 times in these 3 verses. The image of all the nations gathering against God’s people appears in Psalms 2, 46, 48; Isaiah 29:1-8; Ezekiel 38-39; Zech 14:1-9. “We are reminded of the world’s furious hostility to the city of God” Kidner, 413-414.

In the name of the LORD I will surely cut them off- “The Hb. verb here is elsewhere translated ‘I circumcised them’!” Broyles, 441.

118:15-18 The right hand of the LORD does valiantly

118:19-21 He enters God's gates with thanksgiving

118:22-29  God made the rejected stone the chief corner stone.

Psalm 118 and the Exodus
118:14, 21 Quote Exodus 15:2

118:15-16 right hand of the LORD- Exodus 15:6, 6, 12

118:23 marvelous- wonders in Exodus 15:11

118:24 The day- Exodus 14:13

118:28 I will extol You- Exodus 15:2

Psalm 118 and Jesus
118:26 Matthew 21:9; Mark 11:9; Luke 19:38; John 12:13

118:22 Matthew 21:42; Mark 12:10-11; Luke 20:17; Acts 4:11; I Peter 2:7

118:17-18 were some of Jesus' last words ever and they anticipate HIs resurrection.