You can find a YouTube playlist here with many of the songs suggested below.
There are some great songs related to the reading from Acts which work well as gathering songs today and talk of Christ as our cornerstone, such as Christ is made the sure foundation (CH 200 / MP 73), Cornerstone (CCLI) and Christ is our cornerstone (NEH 206). Apart from that it is still good to explore seasonal Easter songs like Alleluia! Alleluia! Hearts to heaven and voices raise (CH 427), Alleluia, alleluia, give thanks to the risen Lord (MP 30), The day of resurrection (CH 413), Great things (CCLI) and Praise the King (CCLI). If you used any of the more contemporary hymns on Easter Sunday such as Christ is alive, and the universe must celebrate (CH 422), Away with gloom, away with doubt (CH 418), Earth, earth, awake; your praises sing (CH 420) or Christ was raised (Resound) it could also be worth repeating them to help them become part of your congregation’s repertoire.
You can be guaranteed to start a heated debate in the Church of Scotland if you ask what the right tune is for singing Psalm 23. This isn’t even a simple split between congregations as you will find a mix of strongly held views within congregations. The Lord’s my shepherd, I’ll not want, the lyrics for Psalm 23 from the Scottish Psalter, sung to Crimond (CH 14) and Brother James’ Air (CH 16) are probably the most widely known while The Lord’s my shepherd (MP 1008 / PFAS 23F / CCLI / Townend) has become a modern classic. Wiltshire (CH 14) and Orlington (CH 15) are both excellent tunes for these lyrics as well and suit congregations who sing in parts, although it is always confusing that they start with the same four notes.
With so many well known tunes it would be easy not to look at other options but there are lots of wonderful settings in a whole range of styles including His love is my resting place (Kimbrough) which has a light country feel and was written as a response to the pandemic, the Victorian hymn The King of love my shepherd is (CH 462), the well known round The Lord is my shepherd, I’ll walk with him always (Hymnary / PFAS 23K) and a beautiful pentatonic Indonesian song My shepherd Lord, with flute so true of tone (STB 291). The Lord is my shepherd (CH 17) and Shepherd me, O God (PFAS 23H / GIA) are both lovely responsorial settings if you have a choir or soloist to sing the verses, although you could also use the sung responses with spoken verses.
The gospel reading is obviously linked to the psalm so any of the songs suggested above could be considered. Halle, halle, halle (CH 345) is a well known chorus and the additional verses by Marty Haugen would make this very appropriate if you have a soloist who could sing these. Other songs to consider are Father of peace, and God of love (CH 272) which links Christ as shepherd with the resurrection story, In heavenly love abiding (CH 551 / MP 331) looks at it through a more pastoral lens and Shepherd (CCLI) which gives a sense of a personal response and faith in the Lord.
I already mentioned a few songs in the gathering section which link to Acts and the idea of Christ as cornerstone and you could use any of them here as well. In Christ alone (MP 1072 / CCLI / Getty) is another well known song which references this while also tying it into the Easter story. O Day of joy and wonder (CH 582) is a Pentecost song but v2 is very relevant as it talks about “the men who once were cowards, are brave beyond compare”. You laid aside your majesty (MP 795 / CCLI) speaks more into what Peter is saying in this passage.
An obvious angle on the Epistle is the commandment in v23 and A new commandment (MP 1) or This is my will, my new command (CH 357) would pick this up explicitly. You could also look at songs about how we show love in “truth and action” (v23) such as God of freedom, God of justice (CH 263) and I will sing a song of love (WGRG). There are also a few short songs that would link to this such as Ubi caritas (CH 801), Jesu, Jesu, fill us with your love (Hope) and He came down that we may have love (CH 359).
Songs about God’s love would work well for a sending song. We sing a love that sets all people free (CH 622) is a good contemporary hymn text set to a well known tune and would pick up the call to truth and action from the Epistle. Some more general options could be Love came down (MP 1237 / CCLI), Through the love of God, our Saviour (CH 562), and Here is love vast as the ocean (MP 987 / Hymnary / CCLI) which can be sung either as a Victorian hymn or in the worship song version by Matt Redman. God is so good (You are worthy) (CCLI) would also link with Acts with its reference to cornerstone in v3. What wondrous love is this (CH 395) or God loved the world so much (WGRG recording and lyrics) are both excellent texts set to one of the best Sacred Harp melodies.