Sifuna led the way with a contribution of Ksh100,000 while Babu Owino added Ksh50,000 to support the cathedral's dedication and the installation of a new bishop.
The congregation erupted in cheers as the two leaders associated with the Linda Mwananchi movement stepped forward to give.
Former Deputy President Rigathi Gachagua was also present at the service turning the occasion into a notable political and spiritual convergence.
His attendance alongside the two opposition-linked figures immediately sparked speculation about possible political realignments ahead of the 2027 general election.
Political observers noted that Gachagua has publicly expressed his willingness to welcome Babu Owino and Sifuna into his Democracy for the Citizens Party saying he would back their candidatures without hesitation should they face difficulties in their current parties.
Sources suggest backchannel discussions between the camps are ongoing.
Babu Owino and Sifuna have built a strong following especially among Nairobi's urban youth and working-class residents.
Owino's grassroots energy in Embakasi East and Sifuna's sharp and articulate advocacy for public interests have made both men among the most recognisable faces of the opposition.
Their presence at the Ruai service alongside Gachagua was not lost on attendees who described the atmosphere as electric.
Hymns and worship mixed with chants of support for the leaders as church officials expressed gratitude for the contributions which will go towards infrastructure and community development programs.
A possible alliance between Gachagua's DCP and the Sifuna-Babu axis could significantly reshape both Nairobi and national politics.
Sifuna's recent speeches calling for unity and accountability have positioned him as a figure capable of drawing support well beyond his senatorial base.
Babu Owino continues to command street-level loyalty that few politicians in Nairobi can match.
Together the two men represent a potent political force that opposition leaders are keen to harness as Kenya moves closer to 2027.
Whether a formal political partnership emerges from these interactions remains to be seen but the signals coming out of Ruai were difficult to ignore.