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On this work we study stability properties of a system of Difference Equations x(t) = ∑^N_k=1 A_k x(t-r_k ), x ∈ Rⁿ, A_k, n x n constant matrices, r_k > 0, in the case that we allow the delays r_k to vary in time. The main result we obtained is that if the above system is stable and the matrices A_k satisfy a commutative condiction A_k A^*_j = A^*_j, j, k = 1, 2, ..., n, then the system x(t) = ∑^N_k=1 A_k x(t-r_k (t)) is also stable.