Do you think that God CAN lie?
I do not think lying is an ability. It is not something about which the word "can" is appropriately used.
I think God can always speak the truth and since "... omnia quaecumque voluit fecit," He need never lie. He never wants to.
Paul, a bondservant of God and an apostle of Jesus Christ, according to the faith of God's elect and the acknowledgment of the truth which accords with godliness, in hope of eternal life which God, who cannot lie, promised before time began (Titus 1:1-2).