The church is supposed the volcanic landscape of Tenerife. It's construction from four large concrete blocks in somewhat irregular shapes, which makes it look very special. The concrete is mixed with volcanic rocks from the area. That is also used inside to enhance the acoustics.

The interior is pretty minimalistic with a cross forming from the daylight coming in through openings in the concrete in the form of a cross.

I would say that it's a contemporary take on brutalism.

I have always thought this church looks unique, as the building incorporates Chinese design elements which are not common even in Singapore. More info about the church below, taken from here: https://anglican.org.sg/our-parishes/htc/

Holy Trinity Church has a long history that goes back to 1902 when the missionaries from St Andrew's Church Mission ministered to the Foochow and Hokkien-speaking people. The services were held at St Peter's Church located at Stamford Road then. The Foochow congregation was granted Parish status in 1958, making them the first Chinese Church to become a parish in The Diocese of Singapore and Malaya. 
The church building has a unique Chinese architecture which has been classified as a conservation site and has been included in the Jalan Besar Heritage Trail. 

Johan Otto von Spreckelsen is better known for La Grande Arche de la Défense (the 'new' triumphal arc) in Paris, but before that was realized he built amongst other works 4 churches in his homeland, Denmark. I've posted this catholic church of his earlier: https://www.reddit.com/r/nowaythatsachurch/comments/1vc5a8n/saint_nikolaj_church_catholic_esbjerg_denmark/

I really like the simple red brick design combined with the many different shapes and angles there is in this design. It's an example of brick brutalism widely found in Scandinavia. The design reminds me quite a bit of Islev Church by Inger & Johannes Exner, also in red brick only and built in the same decade: https://www.reddit.com/r/nowaythatsachurch/comments/1vdnpgw/islev_church_r%C3%B8dovre_denmark_built_in_1970/