The cubic XFeO (X = Sr, Ba) perovskite oxides are studied for their thermodynamic stability in the ferromagnetic phase by using density functional theory calculations. We also explore the elastic properties of these compounds in terms of elastic constants C , bulk modulus B, shear modulus G, anisotropy factor A, Poisson's ratio ν and the B/ G ratio. The electronic properties are examined to elucidate the magnetic order, and the thermoelectric properties of XFeO (X = Sr, Ba) materials are also presented. The modified Becke-Johnson local density approximation scheme has been used to compute the electronic band structure and density of states, which show that these materials are half-metallic ferromagnetic. We study the magnetic properties by computing the crystal field energy (Δ), John-Teller energy (Δ) and the exchange splitting energies Δ( d) and Δ( pd). Our results indicate that strong hybridization causes a decrease in the magnetic moment of Fe, which then produces permanent magnetic moments in the nonmagnetic sites. [ABSTRACT FROM AUTHOR]