Spiritual Songs

From BiblePortal Wikipedia

Hastings' Dictionary of the New Testament [1]

Spiritual songs ( Ephesians 5:19,  Colossians 3:16) cannot be distinguished as such from hymns and psalms (which see). But the meaning of the epithet ‘spiritual’ deserves attention. St. Paul contrasts truly religious thoughts and words inspired by the Holy Spirit with the effusions of drunkards or the odes of heathen poets composed in ecstasy.

A. E. Burn.

International Standard Bible Encyclopedia [2]

( ᾠδαὶ πνευματικαί , ōdaı́ pneumatikaı́ ): ᾠδή , ōdḗ , English "ode," is the general, and generic word for "song," of which "psalms and hymns" are specific varieties (  Ephesians 5:19;  Colossians 3:16 ). It includes all lyric poetry, but is limited by the word "spiritual" to songs inspired by the Holy Spirit and employed in the joyful and devotional expression of the spiritual life. While songs, like psalms and hymns, were used in public worship and praise, they were more intended for, and suited to, personal and private and social use; as, e.g. in family worship, at meals, in the agápai ("love-feasts"), in meetings for prayer and religious intercourse from house to house. The passages above cited give apostolic authority for the use of other than the Old Testament psalms in public praise, and rebuke the narrowness and unbelief that would forever limit the operations of the Holy Spirit and the hymnology of the church to the narrow compass of the Davidic era and the Davidic school of poetry and song.

The "new song" of  Revelation 5:9;  Revelation 14:3 , and "the song of Moses and of the Lamb" ( Revelation 15:3 ), indicate that spiritual songs are to be perpetuated in the eternal melodies of the redeemed.